The invention discloses a wave absorbing device used for eliminating and reducing noise and pulses of hydraulic system fluid. The wave absorbing device used for eliminating and reducing the noise and the pulses of the hydraulic system fluid comprises a cylinder body, a front end cover, a back end cover, inner pipes, gaps relative to the inner pipes, a through hole, damping holes, sound absorption material, damping vibration attenuation material, a sealing ring, an installation screw hole, an anti-skidding bolt and the like. Threads are arranged on the cylinder body, and the front end cover and the back end cover are fixed on the cylinder body. Circular grooves are formed in the front end cover and the back end cover, and inner pipes in different shapes are fixed on the front end cover and the back end cover. Threads are arranged on the back end cover, used for connecting with the cylinder body, and press tightly the front end cover through an inner pipe structure with an outer flanging. The inner pipes are fixed on the end covers in a directly inserted mode, structures such as the gaps and damping holes are arranged on the inner pipes, and through inner pipes with different inner pipes, a cylinder body inner cavity is divided into parts which are communicated through the damping holes. The sound absorption material is formed by non-metal material and attached to the inner side of the cylinder body, vibration attenuation filler is filled in the connection position of the end covers and a shell body, and the wave absorbing device eliminates and reduces the noise and the pressure pulses in different frequency ranges of the hydraulic system fluid and is a wave absorbing device with a wide effective wave absorbing frequency range.