A vehicle behavior control apparatus mounted in a vehicle to control steering of the vehicle. A virtual road outline, which is an outline of a drivable road region where the vehicle will travel, is determined on the basis of detection results from a location sensor. The virtual road outline is reconstructed as a sequence of road segments, such as straight road segments, and right- and left-hand curved road segments. When a current road segment where the vehicle is currently present is a right- or left-hand curved road segment, a subsequent road segment where the vehicle will be present subsequently is tentatively set to a straight road segment until the vehicle reaches the subsequent road segment. The steering angle is controlled so that a virtual-road boundary distance is adapted to a proper distance from the vehicle to a boundary of the virtual road outline situated in front of the vehicle.