On the basis of saving energy, protecting environment, strategy and efficiency, in this paper, the advantage of passive dehumidifying solar house over other traditional dehumidifying systems are expounded. The high humid environment affects not only the thermal comfortableness of indoor people, but also the indoor sanitary condition, human health, indoors electrical equipment and life span of the furniture. This paper presents a passive dehumidifying solar house, the dehumidifying body can be regenerating evaporation by solar energy; new dehumidifying equipment is designed to reduce relative humidity. It is proved that the new dehumidifying body has a very good dehumidifying effect. It will be widely used in some districts.