diff --git a/js/web/script/test-runner-cli.ts b/js/web/script/test-runner-cli.ts
index 03d637b35bc7c..b67e173a22793 100644
--- a/js/web/script/test-runner-cli.ts
+++ b/js/web/script/test-runner-cli.ts
@@ -558,7 +558,9 @@ async function main() {
       if (args.noSandbox) {
         karmaArgs.push('--no-sandbox');
       }
-      if (webgpu || webnn) {
+
+      // When using BrowserStack with Safari, we need NOT to use 'localhost' as the hostname.
+      if (!(browser.startsWith('BS_') && browser.includes('Safari'))) {
         karmaArgs.push('--force-localhost');
       }
       if (webgpu) {