diff --git a/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/alb/application-target-group.ts b/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/alb/application-target-group.ts
index 9c00b275b06e3..a4b8bbcee1c11 100644
--- a/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/alb/application-target-group.ts
+++ b/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/alb/application-target-group.ts
@@ -62,7 +62,7 @@ export interface ApplicationTargetGroupProps extends BaseTargetGroupProps {
 /**
  * Define an Application Target Group
  */
-export class ApplicationTargetGroup extends TargetGroupBase {
+export class ApplicationTargetGroup extends TargetGroupBase implements IApplicationTargetGroup {
   /**
    * Import an existing target group
    */
diff --git a/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/nlb/network-target-group.ts b/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/nlb/network-target-group.ts
index 6c7a3ba27b5c9..dc20f21d6ff52 100644
--- a/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/nlb/network-target-group.ts
+++ b/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/nlb/network-target-group.ts
@@ -34,7 +34,7 @@ export interface NetworkTargetGroupProps extends BaseTargetGroupProps {
 /**
  * Define a Network Target Group
  */
-export class NetworkTargetGroup extends TargetGroupBase {
+export class NetworkTargetGroup extends TargetGroupBase implements INetworkTargetGroup {
   /**
    * Import an existing listener
    */