diff --git a/app/Http/Requests/UpdateAssetRequest.php b/app/Http/Requests/UpdateAssetRequest.php
index 1b379358f9..071134f512 100644
--- a/app/Http/Requests/UpdateAssetRequest.php
+++ b/app/Http/Requests/UpdateAssetRequest.php
@@ -28,6 +28,8 @@ class UpdateAssetRequest extends ImageUploadRequest
      */
     public function rules()
     {
+        $setting = Setting::getSettings();
+
         $rules = array_merge(
             parent::rules(),
             (new Asset)->getRules(),
@@ -37,7 +39,11 @@ class UpdateAssetRequest extends ImageUploadRequest
                 'status_id' => ['integer', 'exists:status_labels,id'],
                 'asset_tag' => [
                     'min:1', 'max:255', 'not_array',
-                    Rule::unique('assets', 'asset_tag')->ignore($this->asset)->withoutTrashed()
+                    Rule::unique('assets', 'asset_tag')->ignore($this->asset)->withoutTrashed(),
+                ],
+                'serial' => [
+                    'nullable', 'string', 'max:255', 'not_array',
+                    $setting->unique_serial=='1' ? Rule::unique('assets', 'serial')->ignore($this->asset)->withoutTrashed() : 'nullable',
                 ],
             ],
         );