A UV-cure adhesive for bonding an optical disk substrates one or both of which having a semitransparent reflective film of silver, a silver alloy, or the like. The thus produced bonded optical disk has a high durability equivalent to those of optical disks using a conventional gold semitransparent reflective film and is free of voids (air bubbles) that might be produced while the optical disk is manufactured by an optical disk manufacturing apparatus. The degradation in reflectance of the semitransparent reflective film can be suppressed even when the produced optical disk is exposed to direct sunlight for a long time. A UV-cure adhesive resin composition for bonding optical disk substrates contains (A) an epoxy (meth)acrylate, 2,2-dimethoxy-1,2-diphenylethan-1-one and (E) a monofunctional, bifunctional, trifunctional (meth)acrylate monomer, and has an electrical resistivity of 1000 MΩ·cm or less at 25° C.