Rrecent years, an air-conditioning system is introduced into various habitation space, such as a housing, office, a motor-car, and the control which takes into consideration not only a temperatures but the thermal comfort is made by various research and development. However, even though thermal comfort is maintained, human's thermal comfort and sensation has various state due to the exposure time in a cirtain thermal environment, psychological influence, and so on. In this paper, transient characteristics of human's theramal comfort and sensation is considered by conducting a subject experiment, and its prediction method for the transient response of human's thermal comfort and sensation is examined.