diff --git a/server/index.js b/server/index.js
index b3c72b3..2f19dcd 100755
--- a/server/index.js
+++ b/server/index.js
@@ -455,11 +455,12 @@ app.delete('/api/projects/:projectName/sessions/:sessionId', authenticateToken,
     }
 });
 
-// Delete project endpoint (only if empty)
+// Delete project endpoint (force=true to delete with sessions)
 app.delete('/api/projects/:projectName', authenticateToken, async (req, res) => {
     try {
         const { projectName } = req.params;
-        await deleteProject(projectName);
+        const force = req.query.force === 'true';
+        await deleteProject(projectName, force);
         res.json({ success: true });
     } catch (error) {
         res.status(500).json({ error: error.message });
diff --git a/server/projects.js b/server/projects.js
index c6deeac..b4606f8 100755
--- a/server/projects.js
+++ b/server/projects.js
@@ -1026,25 +1026,56 @@ async function isProjectEmpty(projectName) {
   }
 }
 
-// Delete an empty project
-async function deleteProject(projectName) {
+// Delete a project (force=true to delete even with sessions)
+async function deleteProject(projectName, force = false) {
   const projectDir = path.join(os.homedir(), '.claude', 'projects', projectName);
-  
+
   try {
-    // First check if the project is empty
     const isEmpty = await isProjectEmpty(projectName);
-    if (!isEmpty) {
+    if (!isEmpty && !force) {
       throw new Error('Cannot delete project with existing sessions');
     }
-    
-    // Remove the project directory
-    await fs.rm(projectDir, { recursive: true, force: true });
-    
-    // Remove from project config
+
     const config = await loadProjectConfig();
+    let projectPath = config[projectName]?.path || config[projectName]?.originalPath;
+
+    // Fallback to extractProjectDirectory if projectPath is not in config
+    if (!projectPath) {
+      projectPath = await extractProjectDirectory(projectName);
+    }
+
+    // Remove the project directory (includes all Claude sessions)
+    await fs.rm(projectDir, { recursive: true, force: true });
+
+    // Delete all Codex sessions associated with this project
+    if (projectPath) {
+      try {
+        const codexSessions = await getCodexSessions(projectPath, { limit: 0 });
+        for (const session of codexSessions) {
+          try {
+            await deleteCodexSession(session.id);
+          } catch (err) {
+            console.warn(`Failed to delete Codex session ${session.id}:`, err.message);
+          }
+        }
+      } catch (err) {
+        console.warn('Failed to delete Codex sessions:', err.message);
+      }
+
+      // Delete Cursor sessions directory if it exists
+      try {
+        const hash = crypto.createHash('md5').update(projectPath).digest('hex');
+        const cursorProjectDir = path.join(os.homedir(), '.cursor', 'chats', hash);
+        await fs.rm(cursorProjectDir, { recursive: true, force: true });
+      } catch (err) {
+        // Cursor dir may not exist, ignore
+      }
+    }
+
+    // Remove from project config
     delete config[projectName];
     await saveProjectConfig(config);
-    
+
     return true;
   } catch (error) {
     console.error(`Error deleting project ${projectName}:`, error);
@@ -1055,17 +1086,17 @@ async function deleteProject(projectName) {
 // Add a project manually to the config (without creating folders)
 async function addProjectManually(projectPath, displayName = null) {
   const absolutePath = path.resolve(projectPath);
-  
+
   try {
     // Check if the path exists
     await fs.access(absolutePath);
   } catch (error) {
     throw new Error(`Path does not exist: ${absolutePath}`);
   }
-  
+
   // Generate project name (encode path for use as directory name)
   const projectName = absolutePath.replace(/\//g, '-');
-  
+
   // Check if project already exists in config
   const config = await loadProjectConfig();
   const projectDir = path.join(os.homedir(), '.claude', 'projects', projectName);
@@ -1076,13 +1107,13 @@ async function addProjectManually(projectPath, displayName = null) {
 
   // Allow adding projects even if the directory exists - this enables tracking
   // existing Claude Code or Cursor projects in the UI
-  
+
   // Add to config as manually added project
   config[projectName] = {
     manuallyAdded: true,
     originalPath: absolutePath
   };
-  
+
   if (displayName) {
     config[projectName].displayName = displayName;
   }
@@ -1214,7 +1245,8 @@ async function getCursorSessions(projectPath) {
 
 
 // Fetch Codex sessions for a given project path
-async function getCodexSessions(projectPath) {
+async function getCodexSessions(projectPath, options = {}) {
+  const { limit = 5 } = options;
   try {
     const codexSessionsDir = path.join(os.homedir(), '.codex', 'sessions');
     const sessions = [];
@@ -1279,8 +1311,8 @@ async function getCodexSessions(projectPath) {
     // Sort sessions by last activity (newest first)
     sessions.sort((a, b) => new Date(b.lastActivity) - new Date(a.lastActivity));
 
-    // Return only the first 5 sessions for performance
-    return sessions.slice(0, 5);
+    // Return limited sessions for performance (0 = unlimited for deletion)
+    return limit > 0 ? sessions.slice(0, limit) : sessions;
 
   } catch (error) {
     console.error('Error fetching Codex sessions:', error);
diff --git a/src/components/Sidebar.jsx b/src/components/Sidebar.jsx
index 35a56a2..e558a9f 100644
--- a/src/components/Sidebar.jsx
+++ b/src/components/Sidebar.jsx
@@ -6,7 +6,7 @@ import { Badge } from './ui/badge';
 import { Input } from './ui/input';
 import { useTranslation } from 'react-i18next';
 
-import { FolderOpen, Folder, Plus, MessageSquare, Clock, ChevronDown, ChevronRight, Edit3, Check, X, Trash2, Settings, FolderPlus, RefreshCw, Sparkles, Edit2, Star, Search } from 'lucide-react';
+import { FolderOpen, Folder, Plus, MessageSquare, Clock, ChevronDown, ChevronRight, Edit3, Check, X, Trash2, Settings, FolderPlus, RefreshCw, Sparkles, Edit2, Star, Search, AlertTriangle } from 'lucide-react';
 import { cn } from '../lib/utils';
 import ClaudeLogo from './ClaudeLogo';
 import CursorLogo from './CursorLogo.jsx';
@@ -80,6 +80,9 @@ function Sidebar({
   const [editingSessionName, setEditingSessionName] = useState('');
   const [generatingSummary, setGeneratingSummary] = useState({});
   const [searchFilter, setSearchFilter] = useState('');
+  const [deletingProjects, setDeletingProjects] = useState(new Set());
+  const [deleteConfirmation, setDeleteConfirmation] = useState(null); // { project, sessionCount }
+  const [sessionDeleteConfirmation, setSessionDeleteConfirmation] = useState(null); // { projectName, sessionId, sessionTitle, provider }
 
   // TaskMaster context
   const { setCurrentProject, mcpServerStatus } = useTaskMaster();
@@ -306,10 +309,15 @@ function Sidebar({
     setEditingName('');
   };
 
-  const deleteSession = async (projectName, sessionId, provider = 'claude') => {
-    if (!confirm(t('messages.deleteSessionConfirm'))) {
-      return;
-    }
+  const showDeleteSessionConfirmation = (projectName, sessionId, sessionTitle, provider = 'claude') => {
+    setSessionDeleteConfirmation({ projectName, sessionId, sessionTitle, provider });
+  };
+
+  const confirmDeleteSession = async () => {
+    if (!sessionDeleteConfirmation) return;
+
+    const { projectName, sessionId, provider } = sessionDeleteConfirmation;
+    setSessionDeleteConfirmation(null);
 
     try {
       console.log('[Sidebar] Deleting session:', { projectName, sessionId, provider });
@@ -343,18 +351,26 @@ function Sidebar({
     }
   };
 
-  const deleteProject = async (projectName) => {
-    if (!confirm(t('messages.deleteProjectConfirm'))) {
-      return;
-    }
+  const deleteProject = (project) => {
+    const sessionCount = getAllSessions(project).length;
+    setDeleteConfirmation({ project, sessionCount });
+  };
+
+  const confirmDeleteProject = async () => {
+    if (!deleteConfirmation) return;
+
+    const { project, sessionCount } = deleteConfirmation;
+    const isEmpty = sessionCount === 0;
+
+    setDeleteConfirmation(null);
+    setDeletingProjects(prev => new Set([...prev, project.name]));
 
     try {
-      const response = await api.deleteProject(projectName);
+      const response = await api.deleteProject(project.name, !isEmpty);
 
       if (response.ok) {
-        // Call parent callback if provided
         if (onProjectDelete) {
-          onProjectDelete(projectName);
+          onProjectDelete(project.name);
         }
       } else {
         const error = await response.json();
@@ -364,6 +380,12 @@ function Sidebar({
     } catch (error) {
       console.error('Error deleting project:', error);
       alert(t('messages.deleteProjectError'));
+    } finally {
+      setDeletingProjects(prev => {
+        const next = new Set(prev);
+        next.delete(project.name);
+        return next;
+      });
     }
   };
 
@@ -488,6 +510,110 @@ function Sidebar({
         document.body
       )}
 
+      {/* Delete Confirmation Modal */}
+      {deleteConfirmation && ReactDOM.createPortal(
+        <div className="fixed inset-0 bg-black/60 backdrop-blur-sm flex items-center justify-center z-50 p-4">
+          <div className="bg-card border border-border rounded-xl shadow-2xl max-w-md w-full overflow-hidden">
+            <div className="p-6">
+              <div className="flex items-start gap-4">
+                <div className="w-12 h-12 rounded-full bg-red-100 dark:bg-red-900/30 flex items-center justify-center flex-shrink-0">
+                  <AlertTriangle className="w-6 h-6 text-red-600 dark:text-red-400" />
+                </div>
+                <div className="flex-1 min-w-0">
+                  <h3 className="text-lg font-semibold text-foreground mb-2">
+                    {t('deleteConfirmation.deleteProject')}
+                  </h3>
+                  <p className="text-sm text-muted-foreground mb-1">
+                    {t('deleteConfirmation.confirmDelete')}{' '}
+                    <span className="font-medium text-foreground">
+                      {deleteConfirmation.project.displayName || deleteConfirmation.project.name}
+                    </span>?
+                  </p>
+                  {deleteConfirmation.sessionCount > 0 && (
+                    <div className="mt-3 p-3 bg-red-50 dark:bg-red-900/20 border border-red-200 dark:border-red-800 rounded-lg">
+                      <p className="text-sm text-red-700 dark:text-red-300 font-medium">
+                        {t('deleteConfirmation.sessionCount', { count: deleteConfirmation.sessionCount })}
+                      </p>
+                      <p className="text-xs text-red-600 dark:text-red-400 mt-1">
+                        {t('deleteConfirmation.allConversationsDeleted')}
+                      </p>
+                    </div>
+                  )}
+                  <p className="text-xs text-muted-foreground mt-3">
+                    {t('deleteConfirmation.cannotUndo')}
+                  </p>
+                </div>
+              </div>
+            </div>
+            <div className="flex gap-3 p-4 bg-muted/30 border-t border-border">
+              <Button
+                variant="outline"
+                className="flex-1"
+                onClick={() => setDeleteConfirmation(null)}
+              >
+                {t('actions.cancel')}
+              </Button>
+              <Button
+                variant="destructive"
+                className="flex-1 bg-red-600 hover:bg-red-700 text-white"
+                onClick={confirmDeleteProject}
+              >
+                <Trash2 className="w-4 h-4 mr-2" />
+                {t('actions.delete')}
+              </Button>
+            </div>
+          </div>
+        </div>,
+        document.body
+      )}
+
+      {/* Session Delete Confirmation Modal */}
+      {sessionDeleteConfirmation && ReactDOM.createPortal(
+        <div className="fixed inset-0 bg-black/60 backdrop-blur-sm flex items-center justify-center z-50 p-4">
+          <div className="bg-card border border-border rounded-xl shadow-2xl max-w-md w-full overflow-hidden">
+            <div className="p-6">
+              <div className="flex items-start gap-4">
+                <div className="w-12 h-12 rounded-full bg-red-100 dark:bg-red-900/30 flex items-center justify-center flex-shrink-0">
+                  <AlertTriangle className="w-6 h-6 text-red-600 dark:text-red-400" />
+                </div>
+                <div className="flex-1 min-w-0">
+                  <h3 className="text-lg font-semibold text-foreground mb-2">
+                    {t('deleteConfirmation.deleteSession')}
+                  </h3>
+                  <p className="text-sm text-muted-foreground mb-1">
+                    {t('deleteConfirmation.confirmDelete')}{' '}
+                    <span className="font-medium text-foreground">
+                      {sessionDeleteConfirmation.sessionTitle || t('sessions.unnamed')}
+                    </span>?
+                  </p>
+                  <p className="text-xs text-muted-foreground mt-3">
+                    {t('deleteConfirmation.cannotUndo')}
+                  </p>
+                </div>
+              </div>
+            </div>
+            <div className="flex gap-3 p-4 bg-muted/30 border-t border-border">
+              <Button
+                variant="outline"
+                className="flex-1"
+                onClick={() => setSessionDeleteConfirmation(null)}
+              >
+                {t('actions.cancel')}
+              </Button>
+              <Button
+                variant="destructive"
+                className="flex-1 bg-red-600 hover:bg-red-700 text-white"
+                onClick={confirmDeleteSession}
+              >
+                <Trash2 className="w-4 h-4 mr-2" />
+                {t('actions.delete')}
+              </Button>
+            </div>
+          </div>
+        </div>,
+        document.body
+      )}
+
       <div
         className="h-full flex flex-col bg-card md:select-none"
         style={isPWA && isMobile ? { paddingTop: '44px' } : {}}
@@ -718,9 +844,10 @@ function Sidebar({
               const isExpanded = expandedProjects.has(project.name);
               const isSelected = selectedProject?.name === project.name;
               const isStarred = isProjectStarred(project.name);
-              
+              const isDeleting = deletingProjects.has(project.name);
+
               return (
-                <div key={project.name} className="md:space-y-1">
+                <div key={project.name} className={cn("md:space-y-1", isDeleting && "opacity-50 pointer-events-none")}>
                   {/* Project Header */}
                   <div className="group md:group">
                     {/* Mobile Project Item */}
@@ -849,18 +976,16 @@ function Sidebar({
                                       : "text-gray-600 dark:text-gray-400"
                                   )} />
                                 </button>
-                                {getAllSessions(project).length === 0 && (
-                                  <button
+                                <button
                                     className="w-8 h-8 rounded-lg bg-red-500/10 dark:bg-red-900/30 flex items-center justify-center active:scale-90 border border-red-200 dark:border-red-800"
                                     onClick={(e) => {
                                       e.stopPropagation();
-                                      deleteProject(project.name);
+                                      deleteProject(project);
                                     }}
-                                    onTouchEnd={handleTouchClick(() => deleteProject(project.name))}
+                                    onTouchEnd={handleTouchClick(() => deleteProject(project))}
                                   >
                                     <Trash2 className="w-4 h-4 text-red-600 dark:text-red-400" />
                                   </button>
-                                )}
                                 <button
                                   className="w-8 h-8 rounded-lg bg-primary/10 dark:bg-primary/20 flex items-center justify-center active:scale-90 border border-primary/20 dark:border-primary/30"
                                   onClick={(e) => {
@@ -1009,18 +1134,16 @@ function Sidebar({
                             >
                               <Edit3 className="w-3 h-3" />
                             </div>
-                            {getAllSessions(project).length === 0 && (
-                              <div
+                            <div
                                 className="w-6 h-6 opacity-0 group-hover:opacity-100 transition-all duration-200 hover:bg-red-50 dark:hover:bg-red-900/20 flex items-center justify-center rounded cursor-pointer touch:opacity-100"
                                 onClick={(e) => {
                                   e.stopPropagation();
-                                  deleteProject(project.name);
+                                  deleteProject(project);
                                 }}
                                 title={t('tooltips.deleteProject')}
                               >
                                 <Trash2 className="w-3 h-3 text-red-600 dark:text-red-400" />
                               </div>
-                            )}
                             {isExpanded ? (
                               <ChevronDown className="w-4 h-4 text-muted-foreground group-hover:text-foreground transition-colors" />
                             ) : (
@@ -1152,9 +1275,9 @@ function Sidebar({
                                       className="w-5 h-5 rounded-md bg-red-50 dark:bg-red-900/20 flex items-center justify-center active:scale-95 transition-transform opacity-70 ml-1"
                                       onClick={(e) => {
                                         e.stopPropagation();
-                                        deleteSession(project.name, session.id, session.__provider);
+                                        showDeleteSessionConfirmation(project.name, session.id, sessionName, session.__provider);
                                       }}
-                                      onTouchEnd={handleTouchClick(() => deleteSession(project.name, session.id, session.__provider))}
+                                      onTouchEnd={handleTouchClick(() => showDeleteSessionConfirmation(project.name, session.id, sessionName, session.__provider))}
                                     >
                                       <Trash2 className="w-2.5 h-2.5 text-red-600 dark:text-red-400" />
                                     </button>
@@ -1271,7 +1394,7 @@ function Sidebar({
                                       className="w-6 h-6 bg-red-50 hover:bg-red-100 dark:bg-red-900/20 dark:hover:bg-red-900/40 rounded flex items-center justify-center"
                                       onClick={(e) => {
                                         e.stopPropagation();
-                                        deleteSession(project.name, session.id, session.__provider);
+                                        showDeleteSessionConfirmation(project.name, session.id, sessionName, session.__provider);
                                       }}
                                       title={t('tooltips.deleteSession')}
                                     >
diff --git a/src/i18n/locales/en/sidebar.json b/src/i18n/locales/en/sidebar.json
index eb7a0d9..7789ddb 100644
--- a/src/i18n/locales/en/sidebar.json
+++ b/src/i18n/locales/en/sidebar.json
@@ -98,5 +98,14 @@
   },
   "version": {
     "updateAvailable": "Update available"
+  },
+  "deleteConfirmation": {
+    "deleteProject": "Delete Project",
+    "deleteSession": "Delete Session",
+    "confirmDelete": "Are you sure you want to delete",
+    "sessionCount_one": "This project contains {{count}} conversation.",
+    "sessionCount_other": "This project contains {{count}} conversations.",
+    "allConversationsDeleted": "All conversations will be permanently deleted.",
+    "cannotUndo": "This action cannot be undone."
   }
 }
diff --git a/src/i18n/locales/zh-CN/sidebar.json b/src/i18n/locales/zh-CN/sidebar.json
index e5e3c65..34d52ed 100644
--- a/src/i18n/locales/zh-CN/sidebar.json
+++ b/src/i18n/locales/zh-CN/sidebar.json
@@ -98,5 +98,14 @@
   },
   "version": {
     "updateAvailable": "有可用更新"
+  },
+  "deleteConfirmation": {
+    "deleteProject": "删除项目",
+    "deleteSession": "删除会话",
+    "confirmDelete": "您确定要删除",
+    "sessionCount_one": "此项目包含 {{count}} 个对话。",
+    "sessionCount_other": "此项目包含 {{count}} 个对话。",
+    "allConversationsDeleted": "所有对话将被永久删除。",
+    "cannotUndo": "此操作无法撤销。"
   }
 }
diff --git a/src/utils/api.js b/src/utils/api.js
index 894bce5..7f497cd 100644
--- a/src/utils/api.js
+++ b/src/utils/api.js
@@ -79,8 +79,8 @@ export const api = {
     authenticatedFetch(`/api/codex/sessions/${sessionId}`, {
       method: 'DELETE',
     }),
-  deleteProject: (projectName) =>
-    authenticatedFetch(`/api/projects/${projectName}`, {
+  deleteProject: (projectName, force = false) =>
+    authenticatedFetch(`/api/projects/${projectName}${force ? '?force=true' : ''}`, {
       method: 'DELETE',
     }),
   createProject: (path) =>