The invention relates to a method for making 
fresh water by fan-shaped foldable 
sea ice storage devices. Each fan-shaped foldable 
sea ice storage device is characterized by comprising a bottom cabin plate and four 
enclosure cabin plates, wherein each 
enclosure cabin plate is in the shape of an 
isosceles trapezoid, the bottom cabin plate is in the shape of a square, and the 
enclosure cabin plates are hinged with the bottom cabin; the contact periphery of the enclosure cabin plates and the bottom cabin is provided with a sealing 
gasket; the enclosure cabin plates are provided with synchronous folding strips, and the enclosure cabin plates and bottom cabin plate are respectively provided with a float bowl; a plurality of devices are put on the sea in a planar mode, and 
seawater in the enclosure cabin plates and bottom cabin plate becomes ice when the 
air temperature is lower than 0 DEG C; when the 
air temperature rises, the 
sea ice starts to melt; when the 
seawater is sucked into the float bowl of the bottom cabin plate, the bottom cabin plate sinks, and the enclosure cabin plates are synchronously folded towards the center under the guide of the synchronous folding strips to form a container; when the 
seawater in the container is evacuated, self-reinforced seal of the container is formed under the pressure of the outside seawater; and when the sea ice in the container melts, the 
fresh water is obtained. The invention does not occupy the 
land resources; the devices are foldable, thereby reducing the occupied area on the sea surface; and the invention saves the procedure of dredging and transporting ice, thereby saving abundant human and energy sources.