diff --git a/build.sh b/build.sh
index 5cfe81f..ed7b27f 100755
--- a/build.sh
+++ b/build.sh
@@ -165,7 +165,6 @@ if [ "$BUILD_BINUTILS" == "yes" ] ; then
     ../../ext/binutils-mrisc32/configure \
         --prefix="$PREFIX" \
         --target="$TARGET" \
-        --with-system-zlib \
         --disable-gdb \
         --disable-sim \
         > configure.log 2>&1
diff --git a/docker/Dockerfile b/docker/Dockerfile
index 9f9104b..8fa8904 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -7,6 +7,5 @@ RUN apt-get update \
        curl \
        flex \
        texinfo \
-       zlib1g-dev \
     && rm -rf /var/lib/apt/lists/*