diff --git a/test/js-perf-test/JSTests.json b/test/js-perf-test/JSTests.json
index e2f71e2d20..6c7c8c6a0c 100644
--- a/test/js-perf-test/JSTests.json
+++ b/test/js-perf-test/JSTests.json
@@ -507,6 +507,20 @@
             {"name": "StringLocaleCompare"}
           ]
         },
+        {
+          "name": "StringToLocaleCase",
+          "main": "run.js",
+          "resources": [ "string-toLocaleCase.js" ],
+          "test_flags": [ "string-toLocaleCase" ],
+          "results_regexp": "^%s\\-Strings\\(Score\\): (.+)$",
+          "run_count": 1,
+          "tests": [
+            {"name": "StringToLocaleLowerCase"},
+            {"name": "StringToLocaleUpperCase"},
+            {"name": "StringToLocaleLowerCaseTR"},
+            {"name": "StringToLocaleUpperCaseTR"}
+          ]
+        },
         {
           "name": "StringMatchAll",
           "main": "run.js",
diff --git a/test/js-perf-test/Strings/string-toLocaleCase.js b/test/js-perf-test/Strings/string-toLocaleCase.js
new file mode 100644
index 0000000000..67919fda06
--- /dev/null
+++ b/test/js-perf-test/Strings/string-toLocaleCase.js
@@ -0,0 +1,35 @@
+// Copyright 2019 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+new BenchmarkSuite('StringToLocaleUpperCaseTR', [5], [
+  new Benchmark('StringToLocaleUpperCaseTR', false, false, 0,
+  StringToLocaleUpperCaseTR)
+]);
+new BenchmarkSuite('StringToLocaleLowerCaseTR', [5], [
+  new Benchmark('StringToLocaleLowerCaseTR', false, false, 0,
+  StringToLocaleLowerCaseTR),
+]);
+new BenchmarkSuite('StringToLocaleUpperCase', [5], [
+  new Benchmark('StringToLocaleUpperCase', false, false, 0,
+  StringToLocaleUpperCase)
+]);
+new BenchmarkSuite('StringToLocaleLowerCase', [5], [
+  new Benchmark('StringToLocaleLowerCase', false, false, 0,
+  StringToLocaleLowerCase),
+]);
+
+var shortString = "Îñţérñåţîöñåļîžåţîöñ Ļöçåļîžåţîöñ החןןם שםוןמ Γρεεκ ισ φθν 一二三";
+
+function StringToLocaleUpperCase() {
+  return shortString.toLocaleUpperCase();
+}
+function StringToLocaleLowerCase() {
+  return shortString.toLocaleLowerCase();
+}
+function StringToLocaleUpperCaseTR() {
+  return shortString.toLocaleUpperCase(["tr"]);
+}
+function StringToLocaleLowerCaseTR() {
+  return shortString.toLocaleLowerCase(["tr"]);
+}