The invention discloses a heat-electrolysis coupling system of a heat-storage tank coupling compression type heat pump and an operation method. The heat-electrolysis coupling system comprises a heat storage tank, a hot water pump, a heat storage hot water valve, a first heat release hot water adjusting valve, a second heat release hot water adjusting valve, a hot net heater, a hot user, a hot netcirculating pump, a cold water pump, a heat storage cold water adjusting valve, a first heat release cold water adjusting valve, a second heat release cold water adjusting valve, an evaporator, a throttling valve, a condenser and a compressor. The invention further discloses the operation method of the heat-electrolysis coupling system. According to the heat-electrolysis coupling system, the compression type heat pump is additionally arranged in a cold water pipeline of the heat storage tank, so that the temperature of the cold water entering the heat storage tank is reduced, the temperature difference of the cold water and the hot water of the heat storage tank is expanded, and the water amount of the heat storage tank is reduced under the condition of the same heat storage capacity, so that the volume of the heat storage tank is reduced, and meanwhile, the compression type heat pump consumes part of electric energy, so that the external power supply amount is reduced, and the deep peak shaving performance of a combined heat and power generation unit is improved.