A device for collecting water from atmospheric moisture comprises water absorbing material, a protection wall and a water container. The protection wall is in a porous form. The water absorbing material is made of the temperature responsive polymer with a phase separation temperature, including Poly(N-isopropylacrylamide) (PNIPAM), Poly(vinylphosphonate) and etc. when its temperature is below phase separation temperature, the temperature responsive polymer is in a swollen hydrated state, forming hydrogen bond with water molecules; so as to absorb water from the air. When its temperature is above said phase separation temperature, the temperature responsive polymer is in a shrunken dehydrated state, forming hydrogen bond with other temperature responsive polymer molecules; so as to expel the water to the water container.