diff --git a/lib/src/flutter_web.dart b/lib/src/flutter_web.dart
index 2ba5de0..7f1f372 100644
--- a/lib/src/flutter_web.dart
+++ b/lib/src/flutter_web.dart
@@ -43,8 +43,8 @@
 
   String getUnsupportedImport(Set<String> imports) {
     for (final import in imports) {
-      // All dart: imports are ok;
-      if (import.startsWith('dart:')) {
+      // All dart: imports are ok, except dart:io
+      if (import.startsWith('dart:') && import != 'dart:io') {
         continue;
       }
 
diff --git a/test/flutter_web_test.dart b/test/flutter_web_test.dart
index 925b8b0..89b7561 100644
--- a/test/flutter_web_test.dart
+++ b/test/flutter_web_test.dart
@@ -46,6 +46,9 @@
           equals('package:path'));
       expect(flutterWebManager.getUnsupportedImport({'foo.dart'}),
           equals('foo.dart'));
+      // dart:io is an unsupported package
+      expect(flutterWebManager.getUnsupportedImport({'dart:io'}),
+          equals('dart:io'));
     });
   });