A wiper blade for a wiper system for wiping motor vehicle windows includes a wiper blade rubber squeegee, which has a wiping lip that faces the window, a rear part that faces away from the window, and a tilting connecting element that joins the wiping lip to the rear part. The wiper blade also includes a strip-like elastic supporting element, or at least one spring rail, which stabilizes the wiper blade rubber squeegee. The supporting element can be joined to a wiper arm which can be transversally driven with regard to the longitudinal extension of the wiper blade and which can be tensioned against the window. The wiper blade is additionally provided with a casing or covering which surrounds, at least in sections, the rear part and the supporting element or the at least one spring rail. The casing is provided with a streamlined form, surrounds the rear part, and when viewed in a direction parallel to the window and of the longitudinal extension of the wiper blade, covers the tilting connecting element. Alternately, the covering is held on the at least one spring rail.