To provide an exhaust pipe structure in which the length of the exhaust pipe can be elongated while the total dimension is restricted. Provided is an exhaust pipe structure which includes an upstream-side exhaust pipe connected to exhaust ports of an engine. An exhaust chamber is provided which has an exhaust-gas inlet and an exhaust-gas outlet, and in which the upstream-side exhaust pipe is connected to the exhaust-gas inlet. In addition, the exhaust pipe structure includes a downstream-side exhaust pipe which is connected to the exhaust-gas outlet and which extends in such a direction as to move away from the exhaust ports. In the exhaust pipe structure, the exhaust-gas inlet is formed at a position farther away from the exhaust ports than the exhaust-gas outlet is positioned.