Disclosed are an oxygen-barrier film and an adhesive used therefor. Provided are an adhesive that can be used for the packaging of food and that consists principally of polyester having excellent oxygen-barrier characteristics, and an oxygen-barrier film that is made by using said adhesive. The disclosed oxygen-barrier film is made by using an adhesive that contains: an amorphous polyester polyol produced by the polycondensation of a polyvalent carboxylic acid component including at least one type of an ortho-oriented aromatic dicarboxylic acid or an anhydride thereof, and a polyol including at least one type of compound selected from the group consisting of ethylene glycol, propylene glycol, butylene glycol, neopentyl glycol, and cyclohexane dimethanol; and a curing agent that can react with the amorphous polyester polyol.