A structure pof muffler may include a housing which has a space therein, and has a first side connected to an inlet pipe into which exhaust gas flows, a first baffle which divides an interior of the housing into a front chamber and an intermediate chamber connected to the inlet pipe, a second baffle which divides the interior of the housing into a rear chamber and the intermediate chamber connected to the inlet pipe, and a discharge pipe which is mounted to penetrate the first baffle and the second baffle, and mounted such that a first end of the discharge pipe is positioned in the rear chamber, and a second end of the discharge pipe extends through the front chamber and penetrates the housing.