diff --git a/det-yolov4-training/Dockerfile b/det-yolov4-training/Dockerfile
index 414603d..c14ac4f 100644
--- a/det-yolov4-training/Dockerfile
+++ b/det-yolov4-training/Dockerfile
@@ -1,4 +1,5 @@
 FROM nvidia/cuda:10.1-cudnn7-devel-ubuntu18.04
+ARG PIP_SOURCE=https://pypi.mirrors.ustc.edu.cn/simple
 WORKDIR /darknet
 RUN apt-get update
 RUN apt install -y software-properties-common wget
@@ -10,9 +11,8 @@ RUN wget https://github.com/AlexeyAB/darknet/releases/download/darknet_yolo_v3_o
 RUN rm /usr/bin/python3
 RUN ln -s /usr/bin/python3.7 /usr/bin/python3
 RUN python3 get-pip.py
-RUN pip3 install -i https://pypi.tuna.tsinghua.edu.cn/simple mxnet-cu101==1.5.1 numpy opencv-python
-RUN pip3 install pyyaml watchdog tensorboardX six
-RUN echo '\ndeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic main restricted universe multiverse\ndeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse\ndeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse\ndeb https://mirrors.tuna.tsinghua.edu.cn/ubuntu/ bionic-security main restricted universe multiverse\n' >> /etc/apt/sources.list
+RUN pip3 install -i ${PIP_SOURCE} mxnet-cu101==1.5.1 numpy opencv-python pyyaml watchdog tensorboardX six
+RUN echo '\ndeb https://mirrors.ustc.edu.cn/ubuntu/ bionic main restricted universe multiverse\ndeb https://mirrors.ustc.edu.cn/ubuntu/ bionic-updates main restricted universe multiverse\ndeb https://mirrors.ustc.edu.cn/ubuntu/ bionic-backports main restricted universe multiverse\ndeb https://mirrors.ustc.edu.cn/ubuntu/ bionic-security main restricted universe multiverse\n' >> /etc/apt/sources.list
 ENV DEBIAN_FRONTEND noninteractive
 RUN apt-get update && apt-get install -y libopencv-dev
 COPY . /darknet