A windshield device for a motorcycle includes a front cowl located at a front side of the vehicle body to cover a vehicle body; a windscreen disposed at an upper part of the front cowl so as to be vertically movable; an air introducing port for introduction of air from the front side being formed between a lower end of the windscreen and a front surface of the front cowl; and an air guide for guiding the air introduced through the air introducing port to flow rearwards along a rear surface of the windscreen, wherein the air guide is firmly attached to the rear surface of the windscreen.