The invention discloses a heat storage type domestic central air-conditioning, heat supply and water heating three-purpose machine. The heat storage type domestic central air-conditioning, heat supplyand water heating three-purpose machine comprises a refrigerant, heat supply/air conditioning water circulation and control system, and is characterized by further comprising a domestic hot water heat exchanging and heat storing machine; the domestic hot water heat exchanging and heat storing machine consists of a preceding-stage water heat exchanger, a hot water tank and a domestic hot water heat exchange tube; a refrigerant circulation system comprises a loop which is formed by sequential connection of a compressor, the preceding-stage water heat exchanger, a four-way valve, a water heat exchanger, a throttling valve, an outdoor air heat exchanger, a four-way valve, an air and liquid separator and a compressor; a heat supply/air conditioning water circulation system comprises a loop formed by sequential connection of a circulating water pump, a water access of the water heat exchanger, a coil tube fan and a dual-purpose water tank; a loop for generating domestic hot water by using aheat pump in spring and autumn consists of a circulating water pump, a water access of the water heat exchanger, a hot water tank and a dual-purpose water tank which are connected in sequence; the hot water tank is used for storing heat and supplying domestic hot water; and the heat exchange amount of the preceding-stage water heat exchanger is smaller than 1/5 of that of the water heat exchanger. The three-purpose machine disclosed by the invention has the functions of supplying head, conditioning air and supplying domestic hot water in four seasons, is extremely simple in both structure andcontrol, is high in efficiency and saves energy.