Efficient automatic polishing equipment for machining comprises a bottom plate, a supporting plate device, an electric cylinder device, a push device, an abutting device, a support device, a frame device, a polishing device and a motor device. A first supporting rod and first cross rods are arranged on the bottom plate, the supporting plate device comprises a supporting plate, first rollers and a first support, and the electric cylinder device comprises a first electric cylinder, first fixed rods, a first push rod, a second roller and first vertical rods. The push device comprises a second vertical rod, a second electric cylinder, a second push rod, a push block and a first sliding block, and the abutting device comprises a third vertical rod, a fourth vertical rod, a first spring, an abutting rod, an abutting block and a second sliding block. The support device comprises a second support, a second cross rod and second fixed rods, and the frame device comprises a vertical plate, a first limiting block, a cross plate and a second limiting block. According to the efficient automatic polishing equipment, a mechanical plate part can be effectively fixed, and the polishing position of a plate can be conveniently adjusted, so that the polishing efficiency is high.