The present invention provides a dual-curable adhesive composition, comprising: component (a): an epoxy resin; at least one selected from component (b) and component (c), wherein component (b) is a (meth)acrylate monomer, and component (c) is an oligomer containing a (meth)acryloxy group; component (d): a thermal polymerization catalyst which catalyzes the thermal polymerization reaction of component (a); and component (e): a photo polymerization initiator which initiates the photo polymerization reaction of component (a) and at least one selected from component (b) and component (c), wherein component (e) is a mixture of a cationic photo polymerization initiator and a radical photo polymerization initiator. The dual-curable adhesive composition of the present invention is used for bonding or laminating a transparent substrate with another transparent substrate, or bonding or laminating a transparent substrate with a non-transparent substrate. The present invention also provides a process for bonding substrat
