diff --git a/specification/containerservice/resource-manager/Microsoft.ContainerService/preview/2022-08-02-preview/managedClusters.json b/specification/containerservice/resource-manager/Microsoft.ContainerService/preview/2022-08-02-preview/managedClusters.json
index 656251e2d1d0..58e1563864c3 100644
--- a/specification/containerservice/resource-manager/Microsoft.ContainerService/preview/2022-08-02-preview/managedClusters.json
+++ b/specification/containerservice/resource-manager/Microsoft.ContainerService/preview/2022-08-02-preview/managedClusters.json
@@ -5314,6 +5314,7 @@
       "enum": [
         "Ubuntu",
         "CBLMariner",
+        "Mariner",
         "Windows2019",
         "Windows2022"
       ],