The present invention relates to an adhesive, a preparation method and application thereof, particularly the application for bonding glass fiber composites, and a bonded article obtained by using the adhesive. The adhesive comprises: a polyisocyanate having an isocyanate functionality of not less than 2; an epoxy-modified polyether polyol; a hydroxyl-containing acrylate; a redox catalyst; a silane coupling agent; optionally a polyol containing bisphenol A structure; and optionally a polymer polyol different from the epoxy-modified polyether polyol. The adhesive according to the present invention has the advantages of being insensitive to moisture, good bonding properties and a long pot life.