The present invention provides an adhesive composition (a UV-curable resin composition) comprising a bisphenol type epoxy(meth)acrylate (A), a di(meth)acrylate compound (B) having a cyclic ether structure, and a photo-polymerization initiator (C), and a bonded optical disk which is adhered with a cured product of said adhesive composition. By adhering with said composition optical disk substrates having a translucent reflection film or a total reflection film comprising silver, a silver alloy, or the like, and obtaining a bonded optical disk, high durability equivalent to those of conventional bonded optical disks in which a translucent reflection film of gold is used, and high adhesion strength between a reflection film and an adhesive cured product, and a polycarbonate substrate and an adhesive cured product, can be obtained.