To provide a fender structure for a motorcycle for preventing muddy water or the like running off a rear fender from being splashed on a muffler. A fender structure for a motorcycle is provided with an engine and wheels suspended therefrom. A fender covers the upper portion of the wheel and extends downwardly on the right and left sides. A muffler is positioned below at least one of the right and left edge portions of the fender. The fender structure includes a folded-back portion extending towards the inner side of the muffler from the corresponding edge portion of the fender.