diff --git a/backend/open_webui/routers/users.py b/backend/open_webui/routers/users.py
index a9ac34e2f..295c9eeb1 100644
--- a/backend/open_webui/routers/users.py
+++ b/backend/open_webui/routers/users.py
@@ -288,6 +288,19 @@ async def update_user_by_id(
     form_data: UserUpdateForm,
     session_user=Depends(get_admin_user),
 ):
+    # Prevent modification of the primary admin user by other admins
+    try:
+        first_user = Users.get_first_user()
+        if first_user and user_id == first_user.id and session_user.id != user_id:
+            raise HTTPException(
+                status_code=status.HTTP_403_FORBIDDEN,
+                detail=ERROR_MESSAGES.ACTION_PROHIBITED,
+            )
+    except Exception as e:
+        log.error(f"Error checking primary admin status: {e}")
+        raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail="Could not verify primary admin status.")
+
+
     user = Users.get_user_by_id(user_id)
 
     if user:
@@ -328,6 +341,7 @@ async def update_user_by_id(
     )
 
 
+
 ############################
 # DeleteUserById
 ############################
@@ -335,6 +349,18 @@ async def update_user_by_id(
 
 @router.delete("/{user_id}", response_model=bool)
 async def delete_user_by_id(user_id: str, user=Depends(get_admin_user)):
+    # Prevent deletion of the primary admin user
+    try:
+        first_user = Users.get_first_user()
+        if first_user and user_id == first_user.id:
+            raise HTTPException(
+                status_code=status.HTTP_403_FORBIDDEN,
+                detail=ERROR_MESSAGES.ACTION_PROHIBITED,
+            )
+    except Exception as e:
+        log.error(f"Error checking primary admin status: {e}")
+        raise HTTPException(status_code=status.HTTP_500_INTERNAL_SERVER_ERROR, detail="Could not verify primary admin status.")
+
     if user.id != user_id:
         result = Auths.delete_auth_by_id(user_id)
 
@@ -346,6 +372,7 @@ async def delete_user_by_id(user_id: str, user=Depends(get_admin_user)):
             detail=ERROR_MESSAGES.DELETE_USER_ERROR,
         )
 
+    # Prevent self-deletion
     raise HTTPException(
         status_code=status.HTTP_403_FORBIDDEN,
         detail=ERROR_MESSAGES.ACTION_PROHIBITED,