diff --git a/demo/MMDet_Tutorial.ipynb b/demo/MMDet_Tutorial.ipynb
index f3c48e3c4..c6c19c230 100644
--- a/demo/MMDet_Tutorial.ipynb
+++ b/demo/MMDet_Tutorial.ipynb
@@ -1509,6 +1509,7 @@
         "# Set seed thus the results are more reproducible\n",
         "cfg.seed = 0\n",
         "set_random_seed(0, deterministic=False)\n",
+        "cfg.device = 'cuda'\n",
         "cfg.gpu_ids = range(1)\n",
         "\n",
         "# We can also use tensorboard to log the training process\n",