diff --git a/src/azure-cli/azure/cli/command_modules/appservice/custom.py b/src/azure-cli/azure/cli/command_modules/appservice/custom.py
index fe981c3afdc..1c1dded1c9a 100644
--- a/src/azure-cli/azure/cli/command_modules/appservice/custom.py
+++ b/src/azure-cli/azure/cli/command_modules/appservice/custom.py
@@ -3231,6 +3231,9 @@ def update_functionapp_app_service_plan(cmd, instance, sku=None, number_of_worke
     if number_of_workers is not None:
         number_of_workers = validate_range_of_int_flag('--number-of-workers / --min-instances',
                                                        number_of_workers, min_val=0, max_val=20)
+    if is_plan_flex(cmd, instance):
+        return update_flex_app_service_plan(instance)
+
     return update_app_service_plan(cmd, instance, sku, number_of_workers)
 
 
@@ -5022,6 +5025,20 @@ def create_flex_app_service_plan(cmd, resource_group_name, name, location, zone_
     return LongRunningOperation(cmd.cli_ctx)(poller)
 
 
+def update_flex_app_service_plan(instance):
+    instance.target_worker_count = None
+    instance.target_worker_size = None
+    instance.is_xenon = None
+    instance.hyper_v = None
+    instance.per_site_scaling = None
+    instance.maximum_elastic_worker_count = None
+    instance.elastic_scale_enabled = None
+    instance.is_spot = None
+    instance.target_worker_size_id = None
+    instance.sku.capacity = None
+    return instance
+
+
 def create_functionapp_app_service_plan(cmd, resource_group_name, name, is_linux, sku, number_of_workers=None,
                                         max_burst=None, location=None, tags=None, zone_redundant=False):
     SkuDescription, AppServicePlan = cmd.get_models('SkuDescription', 'AppServicePlan')
@@ -5052,6 +5069,14 @@ def is_plan_consumption(cmd, plan_info):
     return False
 
 
+def is_plan_flex(cmd, plan_info):
+    SkuDescription, AppServicePlan = cmd.get_models('SkuDescription', 'AppServicePlan')
+    if isinstance(plan_info, AppServicePlan):
+        if isinstance(plan_info.sku, SkuDescription):
+            return plan_info.sku.tier.lower() == 'flexconsumption'
+    return False
+
+
 def is_plan_elastic_premium(cmd, plan_info):
     SkuDescription, AppServicePlan = cmd.get_models('SkuDescription', 'AppServicePlan')
     if isinstance(plan_info, AppServicePlan):
diff --git a/src/azure-cli/azure/cli/command_modules/appservice/tests/latest/test_functionapp_commands.py b/src/azure-cli/azure/cli/command_modules/appservice/tests/latest/test_functionapp_commands.py
index 4c4dc0b74cf..b9c37807799 100644
--- a/src/azure-cli/azure/cli/command_modules/appservice/tests/latest/test_functionapp_commands.py
+++ b/src/azure-cli/azure/cli/command_modules/appservice/tests/latest/test_functionapp_commands.py
@@ -853,10 +853,44 @@ def test_functionapp_flex_zone_redundant_not_active(self, resource_group, storag
                                .format(resource_group, functionapp_name, FLEX_ASP_LOCATION_FUNCTIONAPP, storage_account)).get_output_in_json()
 
         server_farm_id =functionapp['properties']['serverFarmId']
-        function_plan = self.cmd('az functionapp plan show --ids {}'
+        function_plan = self.cmd('functionapp plan show --ids {}'
                                .format(server_farm_id)).get_output_in_json()
         self.assertTrue(function_plan['zoneRedundant'] == False) 
 
+    @ResourceGroupPreparer(location=FLEX_ASP_LOCATION_FUNCTIONAPP)
+    @StorageAccountPreparer()
+    def test_functionapp_flex_plan_enable_zone_redundant(self, resource_group, storage_account):
+        functionapp_name = self.create_random_name(
+            'functionapp', 40)
+
+        functionapp = self.cmd('functionapp create -g {} -n {} -f {} -s {} --runtime python --runtime-version 3.11'
+                               .format(resource_group, functionapp_name, FLEX_ASP_LOCATION_FUNCTIONAPP, storage_account)).get_output_in_json()
+
+        server_farm_id = functionapp['properties']['serverFarmId']
+        function_plan = self.cmd('functionapp plan show --ids {}'.format(server_farm_id)).get_output_in_json()
+        self.assertTrue(function_plan['zoneRedundant'] == False) 
+        updated_plan = self.cmd('functionapp plan update --id {} --set zoneRedundant=true'.format(server_farm_id)).get_output_in_json()
+        self.assertTrue(updated_plan['zoneRedundant'] == True)
+        function_plan = self.cmd('functionapp plan show --ids {}'.format(server_farm_id)).get_output_in_json()
+        self.assertTrue(function_plan['zoneRedundant'] == True) 
+
+    @ResourceGroupPreparer(location=FLEX_ASP_LOCATION_FUNCTIONAPP)
+    @StorageAccountPreparer()
+    def test_functionapp_flex_plan_disable_zone_redundant(self, resource_group, storage_account):
+        functionapp_name = self.create_random_name(
+            'functionapp', 40)
+
+        functionapp = self.cmd('functionapp create -g {} -n {} -f {} -s {} --runtime python --runtime-version 3.11 --zone-redundant'
+                               .format(resource_group, functionapp_name, FLEX_ASP_LOCATION_FUNCTIONAPP, storage_account)).get_output_in_json()
+
+        server_farm_id = functionapp['properties']['serverFarmId']
+        function_plan = self.cmd('functionapp plan show --ids {}'.format(server_farm_id)).get_output_in_json()
+        self.assertTrue(function_plan['zoneRedundant'] == True) 
+        updated_plan = self.cmd('functionapp plan update --id {} --set zoneRedundant=false'.format(server_farm_id)).get_output_in_json()
+        self.assertTrue(updated_plan['zoneRedundant'] == False)
+        function_plan = self.cmd('functionapp plan show --ids {}'.format(server_farm_id)).get_output_in_json()
+        self.assertTrue(function_plan['zoneRedundant'] == False) 
+
     @ResourceGroupPreparer(location=FLEX_ASP_LOCATION_FUNCTIONAPP)
     @StorageAccountPreparer()
     def test_functionapp_flex_scale_config(self, resource_group, storage_account):