The invention discloses a metallographic automatic grinding polishing machine and comprises an electric control unit, a hydraulic unit, a cooling water unit, a polishing spindle unit and a rotational grinding disc unit; wherein, the polishing spindle unit (1) is arranged above the rotational grinding disc unit (2); and the polishing spindle unit (1) and the rotational grinding disc unit (2) respectively adopt independent motors for rotation control and play a part in the polishing spindle unit (1) by controlling and outputting processing parameters through the electric control unit, thus achieving the surface grinding polishing treatment of high hardness metal of aluminium alloy, titanium-aluminium alloy, siliconiobium, etc.