The invention relates to metallographic specimen grinding and polishing equipment and an application method thereof. The metallographic specimen grinding and polishing equipment comprises a fixed bottom plate, a position adjusting mechanism, a motor for polishing, a polishing grinding head and a supporting frame, wherein the position adjusting mechanism is used for fixing a metallographic specimen and is connected with the fixed bottom plate in a sliding manner; the supporting frame is mounted on the fixed plate and is used for supporting the motor; the length of the upper end face of the fixed bottom plate is in the longitudinal direction and the width of the upper end face of the fixed bottom plate is in the transverse direction; the position adjusting mechanism comprises a lower slide rail which is fixed on the fixed bottom plate and extends along the transverse direction, a transverse bottom plate which is connected with the lower slide rail in the sliding manner, an upper slide rail which is fixed on the transverse bottom plate and extends along the longitudinal direction, and a longitudinal bottom plate which is connected with the upper slide rail in the sliding manner. According to the metallographic specimen grinding and polishing equipment and the application method thereof provided by the invention, when the large metallographic specimen is polished, the large metallographic specimen is fixed between two clamping seats and the position of the polishing grinding head is adjusted so that polishing can be carried out; the metallographic specimen grinding and polishing equipment is simple in structure and convenient to clamp; the efficiency of grinding and polishing the large metallographic specimen is greatly improved.