diff --git a/lib/ansible/modules/cloud/azure/azure_rm_functionapp.py b/lib/ansible/modules/cloud/azure/azure_rm_functionapp.py
index 233b890214..6e99030ff9 100644
--- a/lib/ansible/modules/cloud/azure/azure_rm_functionapp.py
+++ b/lib/ansible/modules/cloud/azure/azure_rm_functionapp.py
@@ -280,10 +280,18 @@ class AzureRMFunctionApp(AzureRMModuleBase):
 
         function_app_settings = self.necessary_functionapp_settings()
         for app_setting_key in self.app_settings:
-            function_app_settings.append(NameValuePair(
-                name=app_setting_key,
-                value=self.app_settings[app_setting_key]
-            ))
+            found_setting = None
+            for s in function_app_settings:
+                if s.name == app_setting_key:
+                    found_setting = s
+                    break
+            if found_setting:
+                found_setting.value = self.app_settings[app_setting_key]
+            else:
+                function_app_settings.append(NameValuePair(
+                    name=app_setting_key,
+                    value=self.app_settings[app_setting_key]
+                ))
         return function_app_settings
 
     @property
diff --git a/test/integration/targets/azure_rm_functionapp/tasks/main.yml b/test/integration/targets/azure_rm_functionapp/tasks/main.yml
index 027feb7e86..19349495f5 100644
--- a/test/integration/targets/azure_rm_functionapp/tasks/main.yml
+++ b/test/integration/targets/azure_rm_functionapp/tasks/main.yml
@@ -50,6 +50,7 @@
     app_settings:
       hello: world
       things: more stuff
+      FUNCTIONS_EXTENSION_VERSION: "~2"
   register: output
 
 - name: assert the function with app settings was created
@@ -64,6 +65,7 @@
     app_settings:
       hello: world
       things: more stuff
+      FUNCTIONS_EXTENSION_VERSION: "~2"
       another: one
   register: output