diff --git a/lib/cli-engine/cli-engine.js b/lib/cli-engine/cli-engine.js
index b2535d960a2..6a0352399b7 100644
--- a/lib/cli-engine/cli-engine.js
+++ b/lib/cli-engine/cli-engine.js
@@ -20,7 +20,6 @@ const path = require("path");
 const defaultOptions = require("../../conf/default-cli-options");
 const pkg = require("../../package.json");
 const ConfigOps = require("../shared/config-ops");
-const { emitDeprecationWarning } = require("../shared/deprecation-warnings");
 const naming = require("../shared/naming");
 const ModuleResolver = require("../shared/relative-module-resolver");
 const { Linter } = require("../linter");
@@ -621,14 +620,7 @@ class CLIEngine {
         }
     }
 
-    /**
-     * Get rules that the last `executeOn*` methods used.
-     * @returns {Map<string, Rule>} A map of rule Id and rule implementation.
-     * @deprecated
-     */
     getRules() {
-        emitDeprecationWarning("getRules()", "ESLINT_LEGACY_GET_RULES");
-
         const { lastConfigArrays } = internalSlotsMap.get(this);
 
         return new Map(function *() {
@@ -939,32 +931,6 @@ class CLIEngine {
             .toCompatibleObjectAsConfigFileContent();
     }
 
-    /**
-     * Returns rule objects for the given file based on the CLI options.
-     * @param {string} filePath The path of the file to retrieve rules for.
-     * @returns {Map<string, Rule>} A map of rule ID and rule implementation that is used to lint the file.
-     */
-    getRulesForFile(filePath) {
-        const { configArrayFactory, options } = internalSlotsMap.get(this);
-        const absolutePath = path.resolve(options.cwd, filePath);
-
-        if (directoryExists(absolutePath)) {
-            throw Object.assign(
-                new Error("'filePath' should not be a directory path."),
-                { messageTemplate: "print-config-with-directory-path" }
-            );
-        }
-        const configArray = configArrayFactory.getConfigArrayForFile(
-            absolutePath,
-            { ignoreNotFoundError: true }
-        );
-
-        return new Map(function *() {
-            yield* builtInRules;
-            yield* configArray.pluginRules;
-        }());
-    }
-
     /**
      * Checks if a given path is ignored by ESLint.
      * @param {string} filePath The path of the file to check.
diff --git a/lib/shared/deprecation-warnings.js b/lib/shared/deprecation-warnings.js
index 4b6b29a8b2e..e1481a2e9aa 100644
--- a/lib/shared/deprecation-warnings.js
+++ b/lib/shared/deprecation-warnings.js
@@ -25,13 +25,7 @@ const deprecationWarningMessages = {
     ESLINT_PERSONAL_CONFIG_SUPPRESS:
         "'~/.eslintrc.*' config files have been deprecated. " +
         "Please remove it or add 'root:true' to the config files in your " +
-        "projects in order to avoid loading '~/.eslintrc.*' accidentally.",
-    ESLINT_LEGACY_GET_RULES:
-        "'CLIEngine::getRules()' method has been deprecated. " +
-        "ESLint may use plugins that have the same name but different " +
-        "implementations in each target file. This method will be confused in " +
-        "such a case. " +
-        "Please use 'CLIEngine::getRulesForFile(filePath)' method instead."
+        "projects in order to avoid loading '~/.eslintrc.*' accidentally."
 };
 
 /**
diff --git a/tests/lib/cli-engine/cli-engine.js b/tests/lib/cli-engine/cli-engine.js
index 6acfcbae089..99674b8c141 100644
--- a/tests/lib/cli-engine/cli-engine.js
+++ b/tests/lib/cli-engine/cli-engine.js
@@ -3760,63 +3760,6 @@ describe("CLIEngine", () => {
         });
     });
 
-    describe("getRulesForFile()", () => {
-        const root = getFixturePath("get-rules-for-file");
-
-        /** @type {typeof CLIEngine} */
-        let InMemoryCLIEngine;
-
-        beforeEach(() => {
-            InMemoryCLIEngine = defineCLIEngineWithInMemoryFileSystem({
-                cwd: () => root,
-                files: {
-
-                    // `one` directory has own `eslint-plugin-foo`.
-                    "one/node_modules/eslint-plugin-foo/index.js": `exports.rules = {
-                        one: () => ({})
-                    }`,
-                    "one/.eslintrc.json": JSON.stringify({ plugins: ["foo"] }),
-
-                    // `two` directory has own `eslint-plugin-foo`.
-                    "two/node_modules/eslint-plugin-foo/index.js": `exports.rules = {
-                        two: () => ({})
-                    }`,
-                    "two/.eslintrc.json": JSON.stringify({ plugins: ["foo"] }),
-
-                    // for `--plugin` test.
-                    "node_modules/eslint-plugin-bar/index.js": `exports.rules = {
-                        bar: () => ({})
-                    }`
-                }
-            }).CLIEngine;
-        });
-
-        it("should expose the list of built-in rules, and should not throw not-found error even if no config file.", () => {
-            const engine = new InMemoryCLIEngine({ cwd: root });
-
-            assert(engine.getRulesForFile("test.js").has("no-eval"), "'no-eval' rule is present");
-            assert(engine.getRulesForFile("test.js").has("eqeqeq"), "'eqeqeq' rule is present");
-        });
-
-        it("should expose the list of plugin rules that '--plugin' option provided.", () => {
-            const engine = new InMemoryCLIEngine({ cwd: root, plugins: ["bar"] });
-
-            assert(engine.getRulesForFile("test.js").has("bar/bar"), "'bar/bar' rule is present");
-        });
-
-        it("should expose the list of plugin rules as being relative to the file.", () => {
-            const engine = new InMemoryCLIEngine({ cwd: root });
-
-            assert(!engine.getRulesForFile("test.js").has("foo/one"), "'foo/one' rule is NOT present for 'test.js'");
-            assert(!engine.getRulesForFile("test.js").has("foo/two"), "'foo/two' rule is NOT present for 'test.js'");
-            assert(engine.getRulesForFile("one/test.js").has("foo/one"), "'foo/one' rule is present for 'one/test.js'");
-            assert(!engine.getRulesForFile("one/test.js").has("foo/two"), "'foo/two' rule is NOT present for 'one/test.js'");
-            assert(!engine.getRulesForFile("two/test.js").has("foo/one"), "'foo/one' rule is NOT present for 'two/test.js'");
-            assert(engine.getRulesForFile("two/test.js").has("foo/two"), "'foo/two' rule is present for 'two/test.js'");
-        });
-
-    });
-
     describe("isPathIgnored", () => {
         it("should check if the given path is ignored", () => {
             const engine = new CLIEngine({
@@ -4552,26 +4495,6 @@ describe("CLIEngine", () => {
     });
 
     describe("getRules()", () => {
-        it("should emit deprecation warning on called.", async() => {
-            const warningListener = sinon.spy();
-
-            process.on("warning", warningListener);
-            try {
-                const engine = new CLIEngine();
-
-                engine.getRules();
-                engine.getRules();
-
-                // Wait for event emission.
-                await new Promise(resolve => setTimeout(resolve, 0));
-
-                assert.strictEqual(warningListener.callCount, 1);
-                assert.strictEqual(warningListener.args[0][0].code, "ESLINT_LEGACY_GET_RULES");
-            } finally {
-                process.removeListener("warning", warningListener);
-            }
-        });
-
         it("should expose the list of rules", () => {
             const engine = new CLIEngine();