1. An object recognition system of a vehicle, comprising: a detecting unit that detects an object that is present around the vehicle; and an enlarging unit that enlarges the size of the object detected by the detecting unit and recognizes the enlarged object, and determines a direction of enlargement of the object according to at least one indicator comprising at least one of a road marker indicative of a lane boundary and at least one three-dimensional object that extends on the side of a road or a plurality of three-dimensional objects located at intervals on the side of the road, wherein, the enlarging unit enlarges the size of the object in a direction parallel to the indicator.