An increase in cost is minimized while realizing larger capacity. An optical disc 102 includes, from the bottom of the drawing: a substrate 104; a first information recording layer 108 formed on the substrate 104; and a first light transmission layer 110 having a thickness of about 20 .mu.m formed on the first information recording layer 108. A second information recording layer 114 is formed on the first light transmission layer 110, and a second light transmission layer 116 having a thickness of about 90 .mu.m is formed on the second information recording layer 114. A laser beam La is irradiated from the side of the second light transmission layer 116 to allow recording and/or reading of an information signal on/from the first and second information recording layers 108 and 114.