The utility model discloses a silencer, which comprises a connecting cover provided with an air inlet hole, a bottom end disc and a plurality of barrel bodies detachably connected between the connecting cover and the bottom end disc. The barrel bodies are circular-ring-shaped, cavities of the plurality of barrel bodies form a plurality of expansion chambers respectively, adjacent expansion chambers are communicated through an air hole, the air inlet hole is communicated with the outside through the plurality of expansion chambers, the air holes and an exhaust hole, and a connecting portion for being detachably connected with an application device is arranged on the connecting cover. Air flow enters a first expansion chamber from the air inlet hole on the connecting cover, then enters the next expansion chamber after contraction of the air holes and finally is discharged out through the exhaust hole, thereby achieving the sound elimination purpose in the process. The silencer can be dismounted from the application device, and the plurality of barrel bodies, the connecting cover and the bottom end disc are separated to conduct inside cleaning.