The invention belongs to the technical field of water supply and temperature adjustment, and relates to a device and method for supplying water and adjusting air temperature by means of ice water morphologic changes. The device comprises an electric system, a water collection system, a water conveying control system, a water sprinkler system, a freezing and melting control system and a water source requirement position. Underground water and rainwater are collected perennially and stored, freezing is performed layer by layer in winter and water is stored; meanwhile, due to the fact that heat is emitted while freezing is performed, the air temperature of the region is increased; in summer, an ice body slowly melts, grass, trees and crops are irrigated, and meanwhile the air temperature of the region is decreased due to the fact that heat is absorbed while melting is performed. According to the system for regional water supply and air temperature adjustment, the purposes of storing water, irrigating plants, adjusting the air temperature of the region and improving the ecology of the region can be achieved through the device and method, and the device and method are simple in structure, reliable to implement, low in cost and convenient to control.