diff --git a/.eslintrc.js b/.eslintrc.js
index 01c5257b4288..1938dbcfd544 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -6,7 +6,7 @@
  */
 
 const path = require('path');
-const customImportResolver = path.resolve('./eslint_import_resolver');
+const customImportResolver = path.resolve('./eslintImportResolver');
 
 module.exports = {
   extends: [
@@ -89,7 +89,7 @@ module.exports = {
         'scripts/**/*',
         'integration-tests/*/**/*',
         'website/*/**/*',
-        'eslint_import_resolver.js',
+        'eslintImportResolver.js',
       ],
       rules: {
         'prettier/prettier': [
@@ -150,8 +150,8 @@ module.exports = {
           '**/__mocks__/**',
           '**/?(*.)(spec|test).js?(x)',
           'scripts/**',
-          'eslint_import_resolver.js',
-          'test_setup_file.js',
+          'eslintImportResolver.js',
+          'testSetupFile.js',
         ],
       },
     ],
@@ -168,7 +168,7 @@ module.exports = {
         trailingComma: 'all',
       },
     ],
-    'unicorn/filename-case': [2, {case: 'snakeCase'}],
+    'unicorn/filename-case': [1, {case: 'snakeCase'}],
   },
   settings: {
     'import/resolver': {
diff --git a/CHANGELOG.md b/CHANGELOG.md
index c56b24dca680..125f3c0c5737 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,10 @@
   process. It will be available via `process.env.JEST_WORKER_ID`
   ([#5494](https://github.com/facebook/jest/pull/5494))
 
+### Chore & Maintenance
+* `[filenames]` Standardize file names in root ([#5500](https://github.com/facebook/jest/pull/5500))
+
+
 ## jest 22.2.1
 
 ### Fixes
diff --git a/test_utils.js b/TestUtils.js
similarity index 100%
rename from test_utils.js
rename to TestUtils.js
diff --git a/eslint_import_resolver.js b/eslintImportResolver.js
similarity index 100%
rename from eslint_import_resolver.js
rename to eslintImportResolver.js
diff --git a/package.json b/package.json
index f3c86f30b72c..524333ff50b4 100644
--- a/package.json
+++ b/package.json
@@ -132,7 +132,7 @@
     "transform": {
       "^.+\\.js$": "<rootDir>/packages/babel-jest"
     },
-    "setupTestFrameworkScriptFile": "<rootDir>/test_setup_file.js",
+    "setupTestFrameworkScriptFile": "<rootDir>/testSetupFile.js",
     "snapshotSerializers": [
       "<rootDir>/packages/pretty-format/build/plugins/convert_ansi.js"
     ],
diff --git a/packages/jest-cli/src/__tests__/generate_empty_coverage.test.js b/packages/jest-cli/src/__tests__/generate_empty_coverage.test.js
index 74ed06e74992..c8445f016ebc 100644
--- a/packages/jest-cli/src/__tests__/generate_empty_coverage.test.js
+++ b/packages/jest-cli/src/__tests__/generate_empty_coverage.test.js
@@ -11,7 +11,7 @@
 import generateEmptyCoverage from '../generate_empty_coverage';
 
 const os = require('os');
-const {makeGlobalConfig, makeProjectConfig} = require('../../../../test_utils');
+const {makeGlobalConfig, makeProjectConfig} = require('../../../../TestUtils');
 
 jest.mock('jest-runtime', () => {
   // $FlowFixMe requireActual
diff --git a/packages/jest-cli/src/lib/__tests__/is_valid_path.test.js b/packages/jest-cli/src/lib/__tests__/is_valid_path.test.js
index 9132893f1b3a..437a429b5492 100644
--- a/packages/jest-cli/src/lib/__tests__/is_valid_path.test.js
+++ b/packages/jest-cli/src/lib/__tests__/is_valid_path.test.js
@@ -13,7 +13,7 @@ const path = require('path');
 const {
   makeGlobalConfig,
   makeProjectConfig,
-} = require('../../../../../test_utils');
+} = require('../../../../../TestUtils');
 
 const rootDir = path.resolve(path.sep, 'root');
 
diff --git a/packages/jest-config/src/valid_config.js b/packages/jest-config/src/valid_config.js
index d866c8a9087f..4ca0ba8d677d 100644
--- a/packages/jest-config/src/valid_config.js
+++ b/packages/jest-config/src/valid_config.js
@@ -79,7 +79,7 @@ export default ({
   runTestsByPath: false,
   runner: 'jest-runner',
   setupFiles: ['<rootDir>/setup.js'],
-  setupTestFrameworkScriptFile: '<rootDir>/test_setup_file.js',
+  setupTestFrameworkScriptFile: '<rootDir>/testSetupFile.js',
   silent: true,
   skipNodeResolution: false,
   snapshotSerializers: ['my-serializer-module'],
diff --git a/packages/jest-validate/src/__tests__/fixtures/jest_config.js b/packages/jest-validate/src/__tests__/fixtures/jest_config.js
index edbea621e15e..1395c62f0203 100644
--- a/packages/jest-validate/src/__tests__/fixtures/jest_config.js
+++ b/packages/jest-validate/src/__tests__/fixtures/jest_config.js
@@ -105,7 +105,7 @@ const validConfig = {
   rootDir: '/',
   roots: ['<rootDir>'],
   setupFiles: ['<rootDir>/setup.js'],
-  setupTestFrameworkScriptFile: '<rootDir>/test_setup_file.js',
+  setupTestFrameworkScriptFile: '<rootDir>/testSetupFile.js',
   silent: true,
   snapshotSerializers: ['my-serializer-module'],
   testEnvironment: 'jest-environment-jsdom',
diff --git a/test_setup_file.js b/testSetupFile.js
similarity index 100%
rename from test_setup_file.js
rename to testSetupFile.js