To solve the problem that when a large size substrate is polished by preparing a large size pressurizing surface plate by an Oscar type grinding machine, the polished substrate is difficult to achieve required smoothness because smoothnesses at a central portion and a peripheral portion of glass are different, and a polishing time is forcibly elongated in order to achieve the smoothness at the peripheral portion.

During polishing, the temperature of the lower surface of the pressurizing surface plate 2 rises. Thus, the temperature difference between the atmospheric temperature and that of the lower surface of the pressurizing surface plate 2 is caused during polishing. The thermal deformation of the lower surface of the pressurizing surface plate 2 is compensated such that the lower surface of the pressurizing surface plate 2 makes a flat plane during polishing. Therefore, if there is no temperature difference, the pressurizing surface plate 2 is machined so as to have a concave shape. The polishing is carried out by means of the corrected pressure surface plate 2 and the single-side polishing apparatus using the same.