The present invention provides an adhesive for laminates containing, as a main component, an epoxy resin composition comprising an epoxy resin and an epoxy resin-curing agent, the epoxy resin composition being formed into an epoxy resin cured product containing a skeleton structure represented by the formula (1): ##STR00001## in an amount of at least 40% by weight. Since the adhesive of the present invention reveals not only a suitable adhesion to various film materials but also a high gas-barrier property, only a single layer formed therefrom can realize both an excellent gas-barrier property and an excellent adhesion property in combination, so that it is possible to produce a high gas-barrier laminated film for a packaging material without forming a separate gas-barrier layer therein.