The present invention provides an epoxy adhesive composition capable of reducing re-aggregation of an adhesive layer modifier, maintaining favorable viscosity for a long period of time, exhibiting high adhesiveness, and reducing process failures during application of the adhesive. Provided is an epoxy adhesive composition containing: a modified polyvinyl acetal resin having a constitutional unit with an acid-modified group; an adhesive layer modifier; and an epoxy resin, the epoxy adhesive composition having a ratio of an acid-modified group equivalent of the modified polyvinyl acetal resin to an epoxy equivalent of the epoxy resin (acid-modified group equivalent/epoxy equivalent) of 5.0 to 150.0, the epoxy adhesive composition having a number ratio of the acid-modified group to an epoxy group (acid-modified group number/epoxy group number) of 0.0005 to 0.5.