The invention provides a safe metal grinding machine. The safe metal grinding machine comprises a base, clamping devices, an air pump, a mechanical arm, a pneumatic grinding device and a controller, wherein dust collecting devices are arranged on the base; a grinding guide rail is arranged in the base; a guide rail translation device is arranged on the grinding guide rail; the mechanical arm is mounted on the guide rail translation device; a flat fixed plate is arranged at the top of the mechanical arm; the pneumatic grinding device is mounted on the flat fixed plate; a grinding platform is arranged in the base; hydraulic devices are arranged on the periphery of the grinding platform; the clamping devices are mounted above the hydraulic devices; the air pump is arranged in front of the base; the controller is mounted on the outer surface of the base. Compared with the prior art, the safe metal grinding machine has the benefits as follows: the safe metal grinding machine is convenient to use, the mechanical arm is adopted to drive the pneumatic grinding device for grinding so as to avoid danger generated during manual grinding, the dust collecting devices collect dust produced in a grinding process, and dust explosion is prevented.