Muffler used on automobile air inlet system

The utility model discloses a muffler used on an automobile air inlet system, which comprises a body and resonant cavities connected with the body. The muffler is characterized in that the body is one section of an air inlet pipe of an automobile engine, wherein, a cylindrical closed housing is connected to the outer surface of the body in a positioned body; at least an annular clapboard is arranged in the closed housing in the radial direction, so that the closed housing is divided into two resonant cavities; each resonant cavity corresponds to a group of small circular through-holes formed on the circumference of the body; and the two resonant cavities are respectively communicated with the air inlet pipe through a group of small circular through-holes. The muffler has the advantages as follows: at least two cavities are used in parallel, so that enough muffling amount in wide frequency bands can be easily guaranteed, multiple continuous wide frequency resonant bands are effectively eliminated, and resonant noise of the plurality of wide frequency bands is reduced; and the resonant cavities are manufactured into a whole, so that the structure is compact, the muffler is less limited by an engine room arrangement requirement, and the space is effectively utilized.