diff --git a/bricks/form.js b/bricks/form.js
index 3fa2701..8043757 100644
--- a/bricks/form.js
+++ b/bricks/form.js
@@ -74,7 +74,7 @@ bricks.FormBody = class extends bricks.VBox {
 		var fields = this.opts.fields;
 		for (var i=0; i<fields.length; i++){
 			var box;
-			if (! this.opts.input_layout or this.opts.input_layout == 'VBox'){
+			if (! this.opts.input_layout || this.opts.input_layout == 'VBox'){
 				box = new bricks.VBox({height:'auto',overflow:'none'});
 			} else {
 				box = new bricks.HBox({height:'auto',overflow:'none'});