diff --git a/lib/rules/no-reserved-keys.js b/lib/rules/no-reserved-keys.js
index a9fce43ca..5b73d9c1f 100644
--- a/lib/rules/no-reserved-keys.js
+++ b/lib/rules/no-reserved-keys.js
@@ -44,7 +44,7 @@ module.exports = {
     messages: {
       reserved: "Key '{{name}}' is reserved.",
       startsWithUnderscore:
-        "Keys starting with with '_' are reserved in '{{name}}' group."
+        "Keys starting with '_' are reserved in '{{name}}' group."
     }
   },
   /** @param {RuleContext} context */
diff --git a/tests/lib/rules/no-reserved-keys.js b/tests/lib/rules/no-reserved-keys.js
index 49857cd51..02a1e79b9 100644
--- a/tests/lib/rules/no-reserved-keys.js
+++ b/tests/lib/rules/no-reserved-keys.js
@@ -168,7 +168,7 @@ ruleTester.run('no-reserved-keys', rule, {
       parserOptions: { ecmaVersion: 6 },
       errors: [
         {
-          message: "Keys starting with with '_' are reserved in '_foo' group.",
+          message: "Keys starting with '_' are reserved in '_foo' group.",
           line: 4
         }
       ]
@@ -187,7 +187,7 @@ ruleTester.run('no-reserved-keys', rule, {
       parserOptions: { ecmaVersion: 6 },
       errors: [
         {
-          message: "Keys starting with with '_' are reserved in '_foo' group.",
+          message: "Keys starting with '_' are reserved in '_foo' group.",
           line: 5
         }
       ]
@@ -204,7 +204,7 @@ ruleTester.run('no-reserved-keys', rule, {
       parserOptions: { ecmaVersion: 6 },
       errors: [
         {
-          message: "Keys starting with with '_' are reserved in '_foo' group.",
+          message: "Keys starting with '_' are reserved in '_foo' group.",
           line: 4
         }
       ]