The utility model relates to an alloy block surface polishing device and belongs to the technical field of alloy workpiece maintenance equipment. The alloy block surface polishing device comprises supports, a roller, a workbench and a motor, wherein the motor is a direct-current variable-speed motor. The supports are arranged on the workbench. Bearings are arranged on the supports, and the roller is installed on the bearings. One end of one bearing is connected with the motor. A laser transmitter is installed on the support on one side, and a laser signal receiving device is installed in the corresponding position of the support on the other side, and the laser signal receiving device is connected with a control switch of the motor.