The recognition of raised alphanumeric markings on rubber tires for their automatic classification is presented. Raised alphanumeric markings on rubber tires show different characteristics from those of printed characters. In the preprocessing step of the proposed method, we first determine the slope of an arc, along which alphanumerics are marked, using the Hough transform, and align them horizontally. Then we separate each character using vertical and horizontal projections. In the recognition step, to recognize characters hierarchically we use several effective features, such as width of a character, number of cross points, partial projections, and distance features. Computer simulation results show that the proposed system can be successfully applied to automatic classification of rubber tires.