In a tire type determination method, a surface image of a tread portion of a tire mounted on a vehicle is captured by a camera fixed at a predetermined position in a tilted hanger conveyor line, which is located downstream in a vehicle-carrying direction with respect to a position at which the tire of the vehicle is lifted from the ground and starts moving diagonally upward. Further, image information is extracted from the surface image of the tread portion, and a tire type is determined by checking the image information against registered information. A vehicle inspection system includes a tire type determination portion and a vehicle type information obtaining portion so as to determine the tire type using the method. A conformance determination portion determines whether the tire type determined by the tire type determination portion conforms to a specified tire type searched based on the vehicle type information.