diff --git a/src/vs/workbench/api/common/extHost.api.impl.ts b/src/vs/workbench/api/common/extHost.api.impl.ts
index 68f4c433e7f..62b83684bc6 100644
--- a/src/vs/workbench/api/common/extHost.api.impl.ts
+++ b/src/vs/workbench/api/common/extHost.api.impl.ts
@@ -501,6 +501,7 @@ export function createApiFactoryAndRegisterActors(accessor: ServicesAccessor): I
 				return extHostLanguageFeatures.registerInlayHintsProvider(extension, selector, provider);
 			},
 			registerTypeHierarchyProvider(selector: vscode.DocumentSelector, provider: vscode.TypeHierarchyProvider): vscode.Disposable {
+				checkProposedApiEnabled(extension);
 				return extHostLanguageFeatures.registerTypeHierarchyProvider(extension, selector, provider);
 			}
 		};