Abstract: As a high-efficiency heat-exchange unit，heat pipe has wide application in solar water heater. Collector is an important part of solar water heater. The state of the art of all kinds of solar collector with heat pipes is reviewed in this paper. The feasibility of application of heat pump and air conditioning system combined with heat pipe solar water heater in the energy conservation building is discussed. Main issues，which restrain the development of heat pipes solar water heater，are discussed and analyzed.