At the stage where disc substrates are to be manufactured in mass production by using a stamper, a section where pits/lands are not formed is formed in advance as an additional information recording section among recording tracks formed by a recording data sequence of pits/lands. A metal alloy reflection film is coated on the information recording surface including such an additional information recording section 10. Then, thereafter, additional information is recorded in the additional information recording section 10 by forming hole marks 6 by erasing or decreasing a partial area of the metal alloy reflection film. The additional information is recorded in a partial area of recording tracks in the information recording area (the area where information is recorded by a recording data sequence of pits/lands, the area including a content area and a management area such as a lead-in). The hole marks 6 are formed as marks from which logic values that are the same as those of pits are obtained at the time of reproduction.