diff --git a/DEVELOPMENT.md b/DEVELOPMENT.md
index 8680017b..0be9594b 100644
--- a/DEVELOPMENT.md
+++ b/DEVELOPMENT.md
@@ -6,7 +6,7 @@ To run AWS ParallelCluster UI locally, start by setting the following environmen
 export AWS_ACCESS_KEY_ID=[...]
 export AWS_SECRET_ACCESS_KEY=[...]
 export AWS_DEFAULT_REGION=us-east-2
-export API_VERSION="3.8.0"
+export API_VERSION="3.9.0"
 export API_BASE_URL=https://[API_ID].execute-api.us-east-2.amazonaws.com/prod  # get this from ParallelClusterApi stack outputs
 export ENV=dev
 ```
diff --git a/infrastructure/environments/demo-cfn-update-args.yaml b/infrastructure/environments/demo-cfn-update-args.yaml
index 7dfcc8ca..67392a04 100644
--- a/infrastructure/environments/demo-cfn-update-args.yaml
+++ b/infrastructure/environments/demo-cfn-update-args.yaml
@@ -3,7 +3,7 @@ Parameters:
   - ParameterKey: AdminUserEmail
     UsePreviousValue: true
   - ParameterKey: Version
-    ParameterValue: 3.8.0
+    ParameterValue: 3.9.0
   - ParameterKey: InfrastructureBucket
     ParameterValue: BUCKET_URL_PLACEHOLDER
   - ParameterKey: PublicEcrImageUri
diff --git a/infrastructure/parallelcluster-ui.yaml b/infrastructure/parallelcluster-ui.yaml
index c63262d3..99bf1f7f 100644
--- a/infrastructure/parallelcluster-ui.yaml
+++ b/infrastructure/parallelcluster-ui.yaml
@@ -34,7 +34,7 @@ Parameters:
   Version:
     Description: Version of AWS ParallelCluster to deploy
     Type: String
-    Default: 3.8.0
+    Default: 3.9.0
   ImageBuilderVpcId:
     Description: (Optional) Select the VPC to use for building the container images. If not selected, default VPC will be used.
     Type: String