Abstract: A belt drive of an electrical machine has a belt pulley arranged on a driving end of a machine shaft, a coupling connecting the drive pulley with the machine shaft, the coupling having at least one elastic coupling part provided between a driving side and a driven side of the coupling, a mounting part having a bearing pin and mountable on a machine aggregate which is connected with the electrical machine, a drive belt connecting the mounting part with the machine aggregate, and an inner bearing. The belt pulley in order to take up belt pull forces, is mounted through the inner bearing on the bearing pin of the mounting part which is mountable on the machine aggregate through the drive belt.