The disclosure provides a heat source tower heat pump realizing solution regeneration and heat reutilization based on vacuum boiling. It comprises a refrigerant circuit, a solution circuit, a vacuum maintenance circuit, an air circuit, a regenerative solution heating circuit and a cold/hot water circuit. The unit provided by the disclosure regenerates a solution by taking full advantage of the characteristic that the boiling point of a solution will be reduced in vacuum, uses the heat released from the cooling of overheated refrigerant as the heat of solution regeneration and also uses the heat to produce heat supply hot water. While significantly raising the speed of solution regeneration, it also realizes efficient reutilization of solution regeneration heat, thoroughly solves the problem of solution regeneration of the heat pump of heat source tower system, improves the safety and reliability of the heat pump of heat source tower system in various operating conditions and realizes high overall efficiency of the system.