The invention disclose an air conditioning heat pump, which comprises a compressor, a heat exchanger at the side of a heat source, a heat exchanger at the side of a user, a second heat exchanger, a first throttle mechanism, a second throttle mechanism, a third throttle mechanism, a first four-way valve, a second four-way valve, a first flow controlling valve, a second flow controlling valve, a third flow controlling valve, a ninth flow controlling valve and a flash evaporator. In operation, the flash gas generated in the separating and throttling process of the flash evaporator is used for supplying air for the compressor, thus realizing normal operation under high and low temperature working conditions as well as meeting various production needs for domestic hot water, cooling and heating, and so on. With simple structure, reliable operation and low cost, the air conditioning heat pump is especially suitable for small and medium air conditioning heat pumps of civilian use and with a need for domestic hot water.