diff --git a/src/azure-cli/azure/cli/command_modules/resource/custom.py b/src/azure-cli/azure/cli/command_modules/resource/custom.py
index 2b94571fc25..7fcd090c8c5 100644
--- a/src/azure-cli/azure/cli/command_modules/resource/custom.py
+++ b/src/azure-cli/azure/cli/command_modules/resource/custom.py
@@ -893,7 +893,7 @@ def _prepare_deployment_properties_unmodified(cmd, deployment_scope, template_fi
         template_obj = _remove_comments_from_json(_urlretrieve(template_uri).decode('utf-8'), file_path=template_uri)
     elif template_spec:
         template_link = TemplateLink(id=template_spec, mode="Incremental")
-        template_obj = show_resource(cmd=cmd, resource_ids=[template_spec]).properties['template']
+        template_obj = show_resource(cmd=cmd, resource_ids=[template_spec]).properties['mainTemplate']
     else:
         template_content = (
             run_bicep_command(["build", "--stdout", template_file])