The noise of plunger pump is analyzed and divided into human factors and non-human factors. Taking CY14-1B axial piston pump as an example, the working principle is analyzed first, and then the factors causing noise are found out. Finally, some targeted measures are proposed to reduce noise.Status and classification of hydraulic pumpsMechanical transmission, electrical transmission, hydraulic transmission and pneumatic transmission are commonly used in industry at present. Hydraulic transmission is widely used in all kinds of construction machinery because of its high working pressure, transmission power and the weight of the actuator is relatively large, can be continuously variable and so on. And hydraulic transmission in a very important energy conversion element - hydraulic pump, is widely used.Hydraulic pump, as the power unit in the hydraulic system, plays a vital role in the hydraulic system. According to the type can be divided into blade pump, gear pump, plunger pump, screw pump. Among them, the plunger pump is a common, but also widely used high pressure pump, the noise reduction of the plunger pump this problem, there are many scholars and experts are studying.