diff --git a/backend/utils.py b/backend/utils.py
index 4e8e2b4..b1eaf39 100644
--- a/backend/utils.py
+++ b/backend/utils.py
@@ -86,6 +86,10 @@ def move_note(notes_dir: str, old_path: str, new_path: str) -> bool:
     if not old_full_path.exists():
         return False
     
+    # Check if target already exists (prevent overwriting)
+    if new_full_path.exists():
+        return False
+    
     # Invalidate cache for old path
     old_key = str(old_full_path)
     if old_key in _tag_cache:
diff --git a/frontend/app.js b/frontend/app.js
index 8a09198..531550a 100644
--- a/frontend/app.js
+++ b/frontend/app.js
@@ -2615,6 +2615,15 @@ function noteApp() {
             
             if (oldPath === newPath) return;
             
+            // Check if a note with the new name already exists
+            const existingNote = this.notes.find(n => n.path.toLowerCase() === newPath.toLowerCase());
+            if (existingNote) {
+                alert(`A note named "${newName}" already exists in this folder.`);
+                // Reset the name in the UI
+                this.currentNoteName = oldPath.split('/').pop().replace('.md', '');
+                return;
+            }
+            
             // Create new note with same content
             try {
                 const response = await fetch(`/api/notes/${newPath}`, {