The invention relates to a wiper blade (10) in a flat bar construction, having a rubber-elastic wiper strip (14), in the lateral longitudinal grooves (24) of which two band-shaped spring rails (28) which extend next to each other in a parallel manner and which are bent concavely toward a wiper lip (16) are inserted as support elements which protrude laterally out of the longitudinal grooves (24), and which are held together and attached to each other at the ends thereof by end caps (36) which, on the longitudinal sides thereof, have guide profiles (44) having a u-shaped cross section, the side jaws (46, 48, 60) of which are guided on the portions of the associated spring rail (28), which protrude out of the longitudinal grooves (24), wherein the end caps (36) comprise spring tongues having engagement lugs (50, 62) which engage in recesses (30) of the spring rails (28) and attach same in the assembly direction (52). According to the invention, one of the side jaws (46, 48, 60) of each guide profile (44) is designed to be at least partially elastic and is used as spring tongue, and the engagement lug (50, 62) is molded on the yielding portion of the side jaw (46, 48, 60), wherein the height of said engagement lug decreases in the assembly direction (52) and thus forms a striking bevel (54), while the engagement lug (50, 62) drops off steeply in the opposite direction.