Abstract: Navigation in a hierarchical menu on the current smart TVs (STVs) contributes to a poor user experience for older adults. Difficulty with navigation is caused by the design of an interface and users’ mental models. To explore different design possibilities, two types of menu layouts (i.e., mega menus and tiled menus) with tags were designed in this study. An experiment was conducted to investigate the effect of menu layouts on the user experiences of older adults. A manipulation check of both menu layouts was conducted via eye tracking. To understand users’ mental models, a card sorting method with a path diagram was employed. Thirty older adults were recruited in this experiment. The results indicated that a mega menu can reduce the physical effort of pressing keys, whereas a tiled menu achieves higher satisfaction of older adults. However, the mental model similarity between designers and older adults toward mega menus and tiled menus exhibited no significant difference. Older adults with high spatial ability had mental models that were similar to the mental models of designers.