diff --git a/azure-mgmt-network/src/main/java/com/microsoft/azure/management/network/implementation/ApplicationGatewayBackendImpl.java b/azure-mgmt-network/src/main/java/com/microsoft/azure/management/network/implementation/ApplicationGatewayBackendImpl.java
index <HASH>..<HASH> 100644
--- a/azure-mgmt-network/src/main/java/com/microsoft/azure/management/network/implementation/ApplicationGatewayBackendImpl.java
+++ b/azure-mgmt-network/src/main/java/com/microsoft/azure/management/network/implementation/ApplicationGatewayBackendImpl.java
@@ -107,6 +107,10 @@ class ApplicationGatewayBackendImpl
 
     @Override
     public ApplicationGatewayBackendImpl withoutIpAddress(String ipAddress) {
+        if (this.inner().backendAddresses() == null) {
+            return this;
+        }
+
         final List<ApplicationGatewayBackendAddress> addresses = ensureAddresses();
         for (int i = 0; i < addresses.size(); i++) {
             String curIpAddress = addresses.get(i).ipAddress();
backend state should not change in withoutAddress if NOP