The invention relates to a rotor blade (20, 108, 200) of a wind turbine (100), comprising an inner segment (25, 250), in which the rotor blade (20, 108, 200) is fastened to a rotor hub, and an outer segment (24, 240), which is connected to the rotor blade (20, 108, 200) and has a rotor blade tip (21). The rotor blade (20, 108, 200) in the inner segment (25, 250) has, at least partially, a flatback profile (26, 66, 46, 460) having a truncated rear edge (23, 63, 630), and at least one control unit (33, 53, 54, 79, 81) for controlling the trailing flow at the rotor blade (20, 108, 200) is provided on the flatback profile (26, 66, 46, 460).