diff --git a/cluster/gce/coreos/helper.sh b/cluster/gce/coreos/helper.sh
index f251b08b6da..7effed9da06 100755
--- a/cluster/gce/coreos/helper.sh
+++ b/cluster/gce/coreos/helper.sh
@@ -53,7 +53,7 @@ KUBELET_TOKEN: $(yaml-quote ${KUBELET_TOKEN:-})
 KUBE_PROXY_TOKEN: $(yaml-quote ${KUBE_PROXY_TOKEN:-})
 ADMISSION_CONTROL: $(yaml-quote ${ADMISSION_CONTROL:-})
 MASTER_IP_RANGE: $(yaml-quote ${MASTER_IP_RANGE})
-KUBERNETES_MASTER_NAME=$(yaml-quote ${MASTER_NAME})
+KUBERNETES_MASTER_NAME: $(yaml-quote ${MASTER_NAME})
 KUBERNETES_CONTAINER_RUNTIME: $(yaml-quote ${CONTAINER_RUNTIME})
 RKT_VERSION: $(yaml-quote ${RKT_VERSION})
 CA_CERT: $(yaml-quote ${CA_CERT_BASE64})