Abstract: Based on the human factors ability required in human computer interaction(HCI)process of IT products use, this paper gave literature review on the ergonomic research achievements for the elderly group from the fields including human factors, cognitive psychology, developmental psychology etc., aiming to provide theory basis for IT products development and HCI design for the elderly people. The paper found that ageing does not mean overall decline, most of the ability being lost is about fluid intelligence and sense organs(such as eyesight and hearing), whereas crystal intelligence could maintain and even grow. Thus the paper proposed IT products design should take into account the human characteristics of the elderly people in a more comprehensive way so that designers could use more of the maintained abilities and reduce the requirements on the losing ones, which could improve the products usability.