diff --git a/staging/src/k8s.io/apiserver/pkg/server/options/etcd.go b/staging/src/k8s.io/apiserver/pkg/server/options/etcd.go
index 6a0a5891410..83210381b85 100644
--- a/staging/src/k8s.io/apiserver/pkg/server/options/etcd.go
+++ b/staging/src/k8s.io/apiserver/pkg/server/options/etcd.go
@@ -133,7 +133,8 @@ func (s *EtcdOptions) AddFlags(fs *pflag.FlagSet) {
 
 	fs.StringVar(&s.DefaultStorageMediaType, "storage-media-type", s.DefaultStorageMediaType, ""+
 		"The media type to use to store objects in storage. "+
-		"Some resources or storage backends may only support a specific media type and will ignore this setting.")
+		"Some resources or storage backends may only support a specific media type and will ignore this setting. "+
+		"Supported media types: [application/json, application/yaml, application/vnd.kubernetes.protobuf]")
 	fs.IntVar(&s.DeleteCollectionWorkers, "delete-collection-workers", s.DeleteCollectionWorkers,
 		"Number of workers spawned for DeleteCollection call. These are used to speed up namespace cleanup.")
 
diff --git a/staging/src/k8s.io/apiserver/pkg/server/storage/storage_codec.go b/staging/src/k8s.io/apiserver/pkg/server/storage/storage_codec.go
index 96faa171229..4f5a398a087 100644
--- a/staging/src/k8s.io/apiserver/pkg/server/storage/storage_codec.go
+++ b/staging/src/k8s.io/apiserver/pkg/server/storage/storage_codec.go
@@ -46,9 +46,14 @@ func NewStorageCodec(opts StorageCodecConfig) (runtime.Codec, runtime.GroupVersi
 		return nil, nil, fmt.Errorf("%q is not a valid mime-type", opts.StorageMediaType)
 	}
 
-	serializer, ok := runtime.SerializerInfoForMediaType(opts.StorageSerializer.SupportedMediaTypes(), mediaType)
+	supportedMediaTypes := opts.StorageSerializer.SupportedMediaTypes()
+	serializer, ok := runtime.SerializerInfoForMediaType(supportedMediaTypes, mediaType)
 	if !ok {
-		return nil, nil, fmt.Errorf("unable to find serializer for %q", mediaType)
+		supportedMediaTypeList := make([]string, len(supportedMediaTypes))
+		for i, mediaType := range supportedMediaTypes {
+			supportedMediaTypeList[i] = mediaType.MediaType
+		}
+		return nil, nil, fmt.Errorf("unable to find serializer for %q, supported media types: %v", mediaType, supportedMediaTypeList)
 	}
 
 	s := serializer.Serializer