PURPOSE: To prevent noise from leaking from the inside to the outside of a silencer and restrain the generation of the noise caused by the vibration of a silencer body in the exhaust silencer of an engine for vehicle.

CONSTITUTION: In a silencer 4, which is connected to a downstream end section of the exhaust pipe 2, of which the other upperstream end section is connected to the exhaust port of the cylinder section of an engine for motor-cycles and in which the pressure fluctuation of exhaust gas is counteracted and exhaust noise is absorbed, a body 6 is of double structure comprising an inner cylinder 6a and outer cylinder 6b. The space between the inner cylinder 6a and outer cylinder 6b is filled with sound absorbing material 6c, and the outer cylinder 6b is not fixed to the inner cylinder 6a, but is floatably supported on the sound absorbing material 6c. In the case of this silencer 4, the sound absorbing material 6c is provided outside the inner cylinder 6a without clearance, and the pressure wave of the exhaust gas released by a diffuser pipe 2a is not transmitted to the outer cylinder 6b.