To provide a band window including a water cutoff structure capable of easily and surely cutting off water, and a method of manufacturing it.

The band window is configured by arranging window units including a frame body and a panel disposed inside the frame at least either vertically or horizontally, and has a water cutoff member 50 disposed so as to cover a gap between the adjacent window units formed on the outer peripheral end face. The water cutoff member includes: a seal member 52 which has an adhesive on a surface to be turned to the window unit side and is stuck to the window unit so as to cover the gap between the window units; a cover member 51 put on the seal member from the surface side on the opposite side of the surface with the adhesive of the seal member and disposed so as to cover the gap between the window units; and a fixing member 53 fixed to the window unit through the cover member and the seal member.