A heat-pump hot water supply apparatus, for dissolving problems of delaying in heating rise-up time when re-starting, and ill influences upon starting characteristics, due to liquid refrigerant residing in an evaporator when the operation is stepped, within a heat-pump circuit thereof, comprises a heat-pump refrigerant circuit, in which a compressor, a water / refrigerant heat exchanger, a refrigerant adjusting valve, and an evaporator, in series, through refrigerant pipes, a direct hot-water supply circuit, into which is supplied hot water heated, obtained by heating water supplied from an outside via a water pipe by means the water / refrigerant heat exchanger, and a compressor operation controller means for stopping the compressor and also closing the refrigerant adjusting valve when the compressor stops the operation thereof, and for re-starting the compressor after opening the refrigerant adjusting valve when the compressor starts the operation, again, wherein the refrigerant within the evaporator is collected to the compressor side when the operation is stopped, and after stopping, front and back of the evaporator is brought into a sealed condition by means of a refrigerant adjusting valve and a back-flow preventing valve, thereby preventing the refrigerant from residing within the evaporator.