diff --git a/core/v1/types.go b/core/v1/types.go
index 43e70b9bad..c8c9fc451f 100644
--- a/core/v1/types.go
+++ b/core/v1/types.go
@@ -467,7 +467,7 @@ type PersistentVolumeClaimSpec struct {
 	// In the future, we plan to support more data source types and the behavior
 	// of the provisioner may change.
 	// +optional
-	DataSource *TypedLocalObjectReference `json:"dataSource" protobuf:"bytes,7,opt,name=dataSource"`
+	DataSource *TypedLocalObjectReference `json:"dataSource,omitempty" protobuf:"bytes,7,opt,name=dataSource"`
 }
 
 // PersistentVolumeClaimConditionType is a valid value of PersistentVolumeClaimCondition.Type