diff --git a/INSTALL.md b/INSTALL.md
index f8f3414d92833a032e056375353f17b7357b14ba..3a1455e6809abdae04e1ae54f5e6540c2bbf2cfb 100644
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -5,6 +5,7 @@
 - torchvision from master
 - cocoapi
 - yacs
+- matplotlib
 - (optional) OpenCV for the webcam demo
 
 
@@ -12,7 +13,7 @@
 
 ```bash
 # maskrnn_benchmark and coco api dependencies
-pip install ninja yacs cython
+pip install ninja yacs cython matplotlib
 
 # follow PyTorch installation in https://pytorch.org/get-started/locally/
 # we give the instructions for CUDA 9.0