A mobile phase-change heat and cold storage device include heat transfer plates, a bracket, a casing, a main tube, a storage tank, and a phase-change working medium. Heat is stored and released by the phase-change working medium, and the main tube and casing provide an interface between the heat and cold storage device and the outside world. In the process of heat storage, vapor flows through the heat transfer plates via the main tube; heat is transferred to the phase-change working medium via the heat transfer plates, and is transported in a box body to a designated position; cold water flows through the heat transfer plates via the casing; heat is transferred from the phase-change working medium to the cold water via the heat transfer plates to obtain hot water; the phase-change working medium can release heat by exothermic solidification. The process of cold storage is similar thereto.