B Between 1994-1999, students majoring in mechanical engineering, namely Radiks T., David S. and Hery, made a centerless belt grinding machine, which is currently placed in the Production Process Laboratory of the Department of Mechanical Engineering, Trisakti University. The machine has never been used. To function it needs to do some repairs. In addition, once the engine is operating, its performance will be reviewed. In order to determine the performance of the machine, a grinding test was carried out. In its implementation, the workpiece will be grinded from the lathe, which is cylindrical. Indicators of machine performance are seen from the surface roughness and cylindrical workpiece. The quality of the machine measured by using the geometric shape of the workpiece resulting from the machining process can be in the form of non-spherical, cylindrical, surface smoothness and other geometric shapes. Surface roughness and cylindrical belt grinding without center will be compared with the results of the cylindrical grinding process. It is hoped that the machine can function again and its performance is in accordance with the capabilities of grinding machines in general