An optical sheet is formed by laminating, by co-extrusion molding, a first layer containing a polycarbonate resin, a second layer containing a polyamide resin, and a third layer, wherein the second layer is laminated between the first layer and the third layer, the first layer and second layer, and the second layer and third layer can each be peeled at the interface, and the outer surface of the first layer has a fine grooved structure. The optical sheet, which is provided with a plurality of layers in such a way, is capable of retaining, a sufficient amount of heat in a laminate in a mold since the entire sheet can be made thick during melt extrusion molding, and is able to improve the transferability of the fine grooved structure. In addition, the optical sheet can be made thinner by using only the peeled first layer as an optical sheet.