The invention relates to a plunger reciprocating pump which comprises a pump body, a plunger, an inhalation valve bank and an exhaust valve bank. The plunger is glidingly matched in a plunger hole of the pump body, the inhalation valve bank and the exhaust valve bank are arranged in the pump body, and a pump cavity is formed among the plunger, the inhalation valve bank and the exhaust valve bank in the pump body. The plunger reciprocating pump is characterized in that an adjusting plunger component kept on the same central line as the plunger is mounted on the pump body and comprises a sealing packing box, an adjusting plunger, a screw, a spring and an adjusting handle, wherein the sealing packing box is mounted on the pump body and is provided with a hole with a valve seat in the center, a sealing component and a guiding sealing sleeve are mounted in the hole, the outer circumferential wall of the adjusting plunger is mounted in the sealing component and the guiding sealing sleeve, the valve surface of the front end of the adjusting plunger is arranged in the pump cavity and matched with the valve seat in the center of the packing sealing box, and the screw is provided with a lug boss at the front end, a cylinder in the middle and external threads at the tail. The invention has the advantages of great adjusting range, high adjusting accuracy and convenient adjustment and is suitable for adjusting the flow rates of a plurality of drain openings of a multi-cylinder reciprocating pump.