The invention provides an accurate grinding polisher. The accurate grinding polisher comprises a table, a grinding plate, a portal frame, a pressing mechanism, a drive mechanism and a control box, wherein the grinding plate is installed on the table, the portal frame is disposed on the table, the pressing mechanism is mounted on the portal frame, the drive mechanism is installed on the portal frame and used for driving the pressing mechanism, the control box is installed on the portal frame, the portal frame comprises a first supporting arm, a second supporting arm and cross beams, the first supporting arm and the second supporting arm are opposite, the cross beams are arranged at ends of the first supporting arm and the second supporting arm, the ends of the first supporting arm and the second supporting arm are far from the grinding plate, the first supporting arm and the second supporting arm are located on two sides of the grinding plate respectively, the cross beams are located above the grinding plate, and the pressing mechanism, the drive mechanism and the control box are installed on the cross beams. According to the accurate grinding polisher, the portal frame can stably support the pressing mechanism, stability during operation of an air cylinder of the pressing mechanism can be effectively guaranteed, and polishing qualities can be guaranteed.