To prevent cleaning performance over a pane of glass from being impaired, and make the structure simple.

In the window washing device, three washing agent injection holes are formed in one nozzle. A first water attaching point P1 of washing agent from a first washing agent injection hole, falls in a wiping range A1 applicable to the half length for the rear end side of a wiper blade 34 at the side of a driver's seat, and a second water attaching point P2 of washing agent from a second washing agent injection hole, falls in a wiping rage C1 where the wiping range A of the wiper blade 34 at the driver's seat side and a wiping range B2 applicable to the half length for the rear end side of a wiper blade 36, are overlapped. Besides, a third water attaching point P3 of washing agent from a third washing agent injection hole, is so designed as to fall in a wiping range B1 applicable to the half length for the tip end side of time wiper blade 36 at the assistant driver's seat side.