diff --git a/denops/@denops-private/cli_test.ts b/denops/@denops-private/cli_test.ts
index 13594e2d..e3e6e197 100644
--- a/denops/@denops-private/cli_test.ts
+++ b/denops/@denops-private/cli_test.ts
@@ -1,5 +1,5 @@
 // NOTE: Use sinon to stub the getter property.
-// @deno-types="npm:@types/sinon@^17.0.3"
+// @deno-types="npm:@types/sinon@^21.0.0"
 import sinon from "sinon";
 
 import {
diff --git a/denops/@denops-private/worker_test.ts b/denops/@denops-private/worker_test.ts
index d2009376..e481cc47 100644
--- a/denops/@denops-private/worker_test.ts
+++ b/denops/@denops-private/worker_test.ts
@@ -1,4 +1,4 @@
-// @deno-types="npm:@types/sinon@^17.0.3"
+// @deno-types="npm:@types/sinon@^21.0.0"
 import sinon from "sinon";
 import {
   assertEquals,