diff --git a/install.sh b/install.sh
index 302251e..80437b0 100755
--- a/install.sh
+++ b/install.sh
@@ -640,7 +640,7 @@ main() (
   tag=$1
 
   if [ "${install_dir}" = "${DEFAULT_INSTALL_DIR}" ]; then
-    if [ ! -d "${DOCKER_HOME}" ]; then
+    if [ ! -d "${DOCKER_HOME}" ] && ! which docker > /dev/null 2>&1; then
       log_err "docker is not installed; refusing to install to '${install_dir}'"
       exit 1
     fi
@@ -706,4 +706,4 @@ if [ -z "${TEST_INSTALL_SH}" ]; then
   set -u
   main "$@"
 fi
-set -u
\ No newline at end of file
+set -u