In this paper the methods and results of measurements to classify vehicles travelling a roadway, without utilization of a vehicle-mounted device, are described. In this classification method, a shape pattern of the vehicle's height is measured using a pulsed ultrasonic radar sensor. This measured shape pattern is divided into 8 parts of equal length on a time base, and the height value of each of the 8 parts is compared with a table of values stored in advance in a microprocessor. When a pattern match is obtained, the vehicle class is identified. The passing vehicles are separated into four categories: 1) small passenger car, 2) large passenger car, 3) small truck and 4) large truck. This classification is independent of vehicle speed.