Silencer and vehicle including the same

In an embodiment, a silencer of a vehicle's exhaust system for a fuel cell system is capable of reducing high-frequency noise and reducing noise generated from a drain, wherein the silencer includes a housing having an inlet and an outlet, a perforated tube located in the housing, the perforated tube having a plurality of through-holes, at least one baffle interposed between the housing and the perforated tube to partition a space between the housing and the perforated tube into a plurality of resonance chambers, and a cover installed in the housing to support the perforated tube and to partition the most downstream resonance chamber.