diff --git a/server/projects.js b/server/projects.js
index d8ccaeb7b..79db27ffe 100755
--- a/server/projects.js
+++ b/server/projects.js
@@ -2538,6 +2538,44 @@ async function getGeminiCliSessionMessages(sessionId) {
   return [];
 }
 
+async function deleteGeminiCliSession(sessionId) {
+  const geminiTmpDir = path.join(os.homedir(), '.gemini', 'tmp');
+  let projectDirs;
+  try {
+    projectDirs = await fs.readdir(geminiTmpDir);
+  } catch {
+    throw new Error(`Gemini CLI session not found: ${sessionId}`);
+  }
+
+  for (const projectDir of projectDirs) {
+    const chatsDir = path.join(geminiTmpDir, projectDir, 'chats');
+    let chatFiles;
+    try {
+      chatFiles = await fs.readdir(chatsDir);
+    } catch {
+      continue;
+    }
+
+    for (const chatFile of chatFiles) {
+      if (!chatFile.endsWith('.json')) continue;
+      try {
+        const filePath = path.join(chatsDir, chatFile);
+        const data = await fs.readFile(filePath, 'utf8');
+        const session = JSON.parse(data);
+        const fileSessionId = session.sessionId || chatFile.replace('.json', '');
+        if (fileSessionId === sessionId) {
+          await fs.unlink(filePath);
+          return true;
+        }
+      } catch {
+        continue;
+      }
+    }
+  }
+
+  throw new Error(`Gemini CLI session file not found: ${sessionId}`);
+}
+
 export {
   getProjects,
   getSessions,
@@ -2557,5 +2595,6 @@ export {
   deleteCodexSession,
   getGeminiCliSessions,
   getGeminiCliSessionMessages,
+  deleteGeminiCliSession,
   searchConversations
 };
diff --git a/server/routes/gemini.js b/server/routes/gemini.js
index ff7f36633..1d3f6be65 100644
--- a/server/routes/gemini.js
+++ b/server/routes/gemini.js
@@ -1,6 +1,7 @@
 import express from 'express';
 import sessionManager from '../sessionManager.js';
 import { sessionNamesDb } from '../database/db.js';
+import { deleteGeminiCliSession } from '../projects.js';
 
 const router = express.Router();
 
@@ -12,7 +13,18 @@ router.delete('/sessions/:sessionId', async (req, res) => {
             return res.status(400).json({ success: false, error: 'Invalid session ID format' });
         }
 
-        await sessionManager.deleteSession(sessionId);
+        // Try deleting from UI sessions and CLI sessions
+        let deleted = false;
+        try {
+            await sessionManager.deleteSession(sessionId);
+            deleted = true;
+        } catch { }
+
+        try {
+            await deleteGeminiCliSession(sessionId);
+            deleted = true;
+        } catch { }
+
         sessionNamesDb.deleteName(sessionId, 'gemini');
         res.json({ success: true });
     } catch (error) {
diff --git a/src/hooks/useProjectsState.ts b/src/hooks/useProjectsState.ts
index 28cf682e7..f97534e1d 100644
--- a/src/hooks/useProjectsState.ts
+++ b/src/hooks/useProjectsState.ts
@@ -436,6 +436,8 @@ export function useProjectsState({
         prevProjects.map((project) => ({
           ...project,
           sessions: project.sessions?.filter((session) => session.id !== sessionIdToDelete) ?? [],
+          codexSessions: project.codexSessions?.filter((session) => session.id !== sessionIdToDelete) ?? [],
+          geminiSessions: project.geminiSessions?.filter((session) => session.id !== sessionIdToDelete) ?? [],
           sessionMeta: {
             ...project.sessionMeta,
             total: Math.max(0, (project.sessionMeta?.total as number | undefined ?? 0) - 1),