diff --git a/CHANGELOG.md b/CHANGELOG.md
index d8a1714270f7..8214539cd901 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@
 
 - `[jest-snapshot]` Inline snapshots: do not indent empty lines ([#8277](https://github.com/facebook/jest/pull/8277))
 - `[jest-core]` Make `detectOpenHandles` imply `runInBand` ([#8283](https://github.com/facebook/jest/pull/8283))
+- `[jest-haste-map]` Fix the `mapper` option which was incorrectly ignored ([#8299](https://github.com/facebook/jest/pull/8299))
 
 ### Chore & Maintenance
 
diff --git a/packages/jest-haste-map/src/index.ts b/packages/jest-haste-map/src/index.ts
index 5f14909645c7..70965909d79d 100644
--- a/packages/jest-haste-map/src/index.ts
+++ b/packages/jest-haste-map/src/index.ts
@@ -256,6 +256,7 @@ class HasteMap extends EventEmitter {
       forceNodeFilesystemAPI: !!options.forceNodeFilesystemAPI,
       hasteImplModulePath: options.hasteImplModulePath,
       ignorePattern: options.ignorePattern,
+      mapper: options.mapper,
       maxWorkers: options.maxWorkers,
       mocksPattern: options.mocksPattern
         ? new RegExp(options.mocksPattern)