A space between the trailing edge of a front fender and the outer surface of a front pillar lower in the vehicle width direction is covered with a synthetic resin enclosure inserted from the wheel housing side. The upper end of a main body of the enclosure is provided with an upper extending portion extending toward the lower end of the front pillar upper, and a reinforcing rib is formed on the outer surface of the upper extending portion so as to make the reinforcing rib in contact with the inner surface of a projecting portion of the front fender. A pressure applied to the projecting portion of the front fender is transmitted to the front pillar lower via the reinforcing rib, and thus the surface stiffness of the projecting portion of the front fender can be improved without adding a particular reinforcing member.