A knee airbag for a motor vehicle is described. This knee airbag extends in its installed state along a longitudinal direction (X) from a rear end to a front end. The airbag skin (5) of the knee airbag exhibits a front section (20) and a rear section (22) and a connecting line for contouring of the airbag is located on the rear section (22). In order to simplify the assembly of the knee airbag, the connecting line mainly extends transverse to the longitudinal direction (X) and shortens the rear section (22) in longitudinal direction.