The invention relates to a silencer, which comprises a casing, a first baffle plate, a second baffle plate, an air inlet pipe and an air outlet pipe, wherein the first baffle plate and the second baffle plate are positioned in the casing; the air inlet pipe is in an L shape and comprises a first pipe body, a second pipe body and a porous pipe; the first pipe body extends along the axial line of the silencer; the second pipe body is vertical to the first pipe body; the porous pipe is connected with the first pipe body; the second pipe body is provided with an inlet penetrating through the casing; the silencer is also provided with a U-shaped pipe communicating with the porous pipe, and is also provided with a first support rod and a second support rod; the first support rod and the second support rod are welded between the first baffle plate and the second baffle plate, and are respectively positioned at the two sides of the porous pipe. Through such arrangement, the acoustic effect is improved; the anti-deformation capability of the baffle plates is improved.