diff --git a/docker/Dockerfile b/docker/Dockerfile
index ecbb125d9..d262843be 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -1,9 +1,10 @@
-FROM ubuntu:xenial
+FROM ubuntu:bionic
 LABEL maintainer "Kentaro Wada <www.kentaro.wada@gmail.com>"
 
+ENV DEBIAN_FRONTEND=noninteractive
+
 RUN \
   apt-get update -qq && \
-  apt-get upgrade -qq -y && \
   apt-get install -qq -y \
     git \
     python3 \