diff --git a/packages/@aws-cdk/aws-ecr/README.md b/packages/@aws-cdk/aws-ecr/README.md
index 4def96fccebcd..9cdb07602e3fb 100644
--- a/packages/@aws-cdk/aws-ecr/README.md
+++ b/packages/@aws-cdk/aws-ecr/README.md
@@ -30,5 +30,5 @@ is important here):
 
 ```ts
 repository.addLifecycleRule({ tagPrefixList: ['prod'], maxImageCount: 9999 });
-repository.addLifecycleRule({ maxImageAgeDays: cdk.Duration.days(30) });
+repository.addLifecycleRule({ maxImageAge: cdk.Duration.days(30) });
 ```
diff --git a/packages/@aws-cdk/aws-ecr/lib/lifecycle.ts b/packages/@aws-cdk/aws-ecr/lib/lifecycle.ts
index 0174d8391006a..1e3be2a5fb90e 100644
--- a/packages/@aws-cdk/aws-ecr/lib/lifecycle.ts
+++ b/packages/@aws-cdk/aws-ecr/lib/lifecycle.ts
@@ -47,7 +47,7 @@ export interface LifecycleRule {
   /**
    * The maximum number of images to retain
    *
-   * Specify exactly one of maxImageCount and maxImageAgeDays.
+   * Specify exactly one of maxImageCount and maxImageAge.
    */
   readonly maxImageCount?: number;