diff --git a/core/controller/Dockerfile b/core/controller/Dockerfile
index cff07ed0f7d..432ff456c53 100644
--- a/core/controller/Dockerfile
+++ b/core/controller/Dockerfile
@@ -22,30 +22,12 @@ ENV UID=1001 \
 ENV SWAGGER_UI_DOWNLOAD_SHA256=3d7ef5ddc59e10f132fe99771498f0f1ba7a2cbfb9585f9863d4191a574c96e7 \
     SWAGGER_UI_VERSION=3.6.0
 
-###################################################################################################
-# It's needed for lean mode where the controller is also an invoker
-###################################################################################################
-# If you change the docker version here, it has implications on invoker runc support.
-# Docker server version and the invoker docker version must be the same to enable runc usage.
-# If this cannot be guaranteed, set `invoker_use_runc: false` in the ansible env.
-ENV DOCKER_VERSION=18.06.3-ce
-
 RUN apt update &&\
     # Upgrade installed packages to get latest security fixes if the base image does not contain them already.
     apt upgrade -y --no-install-recommends && \
     apt install -y \
      openssl
 
-# Uncomment to fetch latest version of docker instead: RUN wget -qO- https://get.docker.com | sh
-# Install docker client
-RUN curl -sSL -o docker-${DOCKER_VERSION}.tgz https://download.docker.com/linux/static/stable/x86_64/docker-${DOCKER_VERSION}.tgz && \
-    tar --strip-components 1 -xvzf docker-${DOCKER_VERSION}.tgz -C /usr/bin docker/docker && \
-    tar --strip-components 1 -xvzf docker-${DOCKER_VERSION}.tgz -C /usr/bin docker/docker-runc && \
-    rm -f docker-${DOCKER_VERSION}.tgz && \
-    chmod +x /usr/bin/docker && \
-    chmod +x /usr/bin/docker-runc
-##################################################################################################
-
 # Install swagger-ui
 RUN curl -sSL -o swagger-ui-v${SWAGGER_UI_VERSION}.tar.gz --no-verbose https://github.com/swagger-api/swagger-ui/archive/v${SWAGGER_UI_VERSION}.tar.gz && \
     echo "${SWAGGER_UI_DOWNLOAD_SHA256}  swagger-ui-v${SWAGGER_UI_VERSION}.tar.gz" | sha256sum -c - && \
diff --git a/core/invoker/Dockerfile b/core/invoker/Dockerfile
index d154cce9a35..d586a47f1c5 100644
--- a/core/invoker/Dockerfile
+++ b/core/invoker/Dockerfile
@@ -19,7 +19,7 @@ FROM scala
 
 ENV UID=1001 \
     NOT_ROOT_USER=owuser
-    ENV DOCKER_VERSION=18.06.3-ce
+
 # If you change the docker version here, it has implications on invoker runc support.
 # Docker server version and the invoker docker version must be the same to enable runc usage.
 # If this cannot be guaranteed, set `invoker_use_runc: false` in the ansible env.
@@ -30,14 +30,6 @@ RUN apt update &&\
     apt upgrade -y --no-install-recommends && \
     apt install -y \
      openssl
-# Uncomment to fetch latest version of docker instead: RUN wget -qO- https://get.docker.com | sh
-# Install docker client
-RUN curl -sSL -o docker-${DOCKER_VERSION}.tgz https://download.docker.com/linux/static/stable/x86_64/docker-${DOCKER_VERSION}.tgz && \
-    tar --strip-components 1 -xvzf docker-${DOCKER_VERSION}.tgz -C /usr/bin docker/docker && \
-    tar --strip-components 1 -xvzf docker-${DOCKER_VERSION}.tgz -C /usr/bin docker/docker-runc && \
-    rm -f docker-${DOCKER_VERSION}.tgz && \
-    chmod +x /usr/bin/docker && \
-    chmod +x /usr/bin/docker-runc
 
 ADD build/distributions/invoker.tar ./