An improved fender structure for a motorcycle includes a rear fender for covering a rear wheel, and a support stay for supporting the rear fender on a motorcycle body frame. The support stay extends along an inner surface of the rear fender, from the motorcycle body frame to the rear end of the rear fender. The support stay also supports a tail lamp body that is provided on an exterior surface of the rear fender. The front end of the rear fender includes a contact portion that interacts with the motorcycle body frame. The improved fender structure provides sufficient rigidity for a rear end portion of the rear fenders while achieving a simplified fender shape, reducing molding costs, and improving the external appearance. The improved fender structure also permits easy assembly of the rear fender to the motorcycle.