To downsize a parallel wiping type windshield wiper device by guiding a conveying body, which reciprocates a moving body, along a guide rail at the time of providing the device on a surface of a window having a curved surface.

A conveying body 8 is wound around between a driving pulley 6 having a spindle portion 6a and a driven pulley 7 having a spindle portion 7a. The spindles 6a, 7a face a vertical direction. The conveying body 8 is guided by a front auxiliary pulley 9 and a rear auxiliary pulley 10 in the condition of that a portion of the conveying body 8 is displaced in front and rear directions and vertical direction. Furthermore, a conveying body 8 contacts with and is guided by a first guide rail 2 and a second guide rail 3. A length of the conveying body 8 is set up so that the conveying body 8 may be in a substantially strained state under the condition where it connects with a moving body 4 which moves on the first guide rail 2 and the second guide rail 3.