diff --git a/elastalert/schema.yaml b/elastalert/schema.yaml
index c4a9242b..925cf07a 100644
--- a/elastalert/schema.yaml
+++ b/elastalert/schema.yaml
@@ -471,7 +471,7 @@ properties:
             required: [field]
             properties:
               field: {type: string, minLength: 1}
-  gelf_log_level: {type: integer}
+  gelf_log_level: {type: integer, enum: ['0', 1', '2', '3', '4', '5', '6', '7']}
   gelf_http_headers:
     type: object
     minProperties: 1