An exhaust apparatus for internal combustion engines which can reduce exhaust noises, its weight and production cost with no need to provide a sub-muffler. The exhaust apparatus is provided with an inner pipe having the upstream open end and the downstream open end is disposed in the tail pipe, and the upstream open end of the inner pipe is protruded outwardly from the inside of the tail pipe to be extended into the resonance chamber, and thus the upstream open end is closed by the resonance chamber defined by the outer shell of the muffler, the end plate, and the partition plate.