This paper aims to propose a cognitive evaluation model to be utilized in designing game devices and developing relevant software with the purpose of the prevention of dementia of the elderly among various types of serious games for the elderly intending to improve their physical, mental or social capability. Firstly, a serious game for the elderly has been developed based on the guidelines of the areas pertaining to existing hardware, software and contents. Secondly, a pre-experiment of the game targeting specialists has been conducted in order to re-establish a cognitive evaluation model for the developed result. Thirdly, the cognitive evaluation model for the serious game for the elderly that intends to improve their cognitive capacity has been materialized based on the experiment results. Given the fact that the scope of game contents, most of which used to be focused on teenagers, have been gradually expanding to cover wider range of social classes than ever before, it is expected that the results of this study could be utilized as a model that can verify the games and their contents with special purposes based on the cognitive evaluation of the users.