diff --git a/drivers/video/video.c b/drivers/video/video.c
index 508e062e63..bf4adecba3 100644
--- a/drivers/video/video.c
+++ b/drivers/video/video.c
@@ -1046,6 +1046,7 @@ static int video_close(FAR struct file *filep)
   nxmutex_lock(&priv->lock_open_num);
   if (priv->open_num == 0)
     {
+      nxmutex_unlock(&priv->lock_open_num);
       return OK;
     }