Starting from human design perspective of the product and using ergonomics knowledge, measurement method and model method are adapted to analyze harmonious relations between people in the sedentary state and office chairs in various parts. The research aims at how to correctly apply the theory of ergonomics in the design of new product development to ensure that the technical problems related to design fitness. And for the “Chair family ”--- the sedentary population, the user-friendly design elements of health office chairs, methods and performance evaluation are studied and summarized as well.