diff --git a/pkg/dartdev/bin/dartdev.dart b/pkg/dartdev/bin/dartdev.dart
index 7c096eef57c1..10751b1ca730 100644
--- a/pkg/dartdev/bin/dartdev.dart
+++ b/pkg/dartdev/bin/dartdev.dart
@@ -5,8 +5,15 @@
 import 'dart:isolate';
 
 import 'package:dartdev/dartdev.dart';
+import 'package:pub/src/http.dart';
 
 /// The entry point for dartdev.
 Future<void> main(List<String> args, SendPort? port) async {
-  await runDartdev(args, port);
+  try {
+    await runDartdev(args, port);
+  } finally {
+    // TODO(https://github.com/dart-lang/pub/issues/4209). Handle this in a more
+    // structured way.
+    globalHttpClient.close();
+  }
 }