The invention relates to a high-volume-efficiency combined-type pump valve of a reciprocating pump. The high-volume-efficiency combined-type pump valve of the reciprocating pump comprises the reciprocating pump, a liquid draining valve core, a liquid draining valve base, a liquid draining valve cover, a liquid draining spring, a gland and a pneumatic assembly, wherein the liquid draining valve core, the liquid draining valve base, the liquid draining valve cover, the liquid draining spring, the gland and the pneumatic assembly are installed on the reciprocating pump. The gland is fixed at one end of a pump body of the reciprocating pump. The liquid draining valve cover is fixed on the pump body of the reciprocating pump and located between the gland and a high-pressure liquid draining cavity of the reciprocating pump. The liquid draining valve core comprises a valve core end and a valve core cover. The liquid draining valve cover is fixed between the liquid draining valve base and the pump body of the reciprocating pump. The free end of the valve core cover moves along a gap. The liquid draining valve core and the gland are respectively provided with a channel. After being sequentially connected, the channels are communicated with the pneumatic assembly. According to the high-volume-efficiency combined-type pump valve of the reciprocating pump, the technical problems that an existing reciprocating pump is low in volume efficiency, and air locking exists are solved, the requirements for medium condensate depression and the heat-insulating property of the pump body in the operation of the carbon dioxide reciprocating pump are reduced, and the aims of saving energy, reducing emission and saving the cost are achieved.