diff --git a/azurerm/resource_arm_kubernetes_cluster.go b/azurerm/resource_arm_kubernetes_cluster.go
index 555ba2aaa3e7..ba519748f6e2 100644
--- a/azurerm/resource_arm_kubernetes_cluster.go
+++ b/azurerm/resource_arm_kubernetes_cluster.go
@@ -37,8 +37,7 @@ func resourceArmKubernetesCluster() *schema.Resource {
 
 			"dns_prefix": {
 				Type:     schema.TypeString,
-				Optional: true,
-				Computed: true,
+				Required: true,
 			},
 
 			"fqdn": {
diff --git a/website/docs/r/kubernetes_cluster.html.markdown b/website/docs/r/kubernetes_cluster.html.markdown
index f59168e84d0e..d7f3c5ee6eb1 100644
--- a/website/docs/r/kubernetes_cluster.html.markdown
+++ b/website/docs/r/kubernetes_cluster.html.markdown
@@ -89,7 +89,7 @@ The following arguments are supported:
 
 * `resource_group_name` - (Required) Specifies the resource group where the resource exists. Changing this forces a new resource to be created.
 
-* `dns_prefix` - (Optional) DNS prefix specified when creating the managed cluster.
+* `dns_prefix` - (Required) DNS prefix specified when creating the managed cluster.
 
 * `kubernetes_version` - (Optional) Version of Kubernetes specified when creating the AKS managed cluster. If not specified, the latest recommended version will be used at provisioning time (but won't auto-upgrade).