diff --git a/cmd/kubeadm/app/phases/kubelet/flags.go b/cmd/kubeadm/app/phases/kubelet/flags.go
index c3a047613d..27c2a9948c 100644
--- a/cmd/kubeadm/app/phases/kubelet/flags.go
+++ b/cmd/kubeadm/app/phases/kubelet/flags.go
@@ -63,7 +63,7 @@ func WriteKubeletDynamicEnvFile(cfg *kubeadmapi.ClusterConfiguration, nodeReg *k
 	}
 	stringMap := buildKubeletArgMap(flagOpts)
 	argList := kubeadmutil.BuildArgumentListFromMap(stringMap, nodeReg.KubeletExtraArgs)
-	envFileContent := fmt.Sprintf("%s=%s\n", constants.KubeletEnvFileVariableName, strings.Join(argList, " "))
+	envFileContent := fmt.Sprintf("%s=%q\n", constants.KubeletEnvFileVariableName, strings.Join(argList, " "))
 
 	return writeKubeletFlagBytesToDisk([]byte(envFileContent), kubeletDir)
 }