Using aqueous N-(2-methacryloyloxyethyl)-2-pyrrolidone(MEP)as a new dentin primer, we examined the adhesion of composite resin to dentin with light curing bonding agents of commercial and experimental origin.The MEP primer improved the tensile bond strength significantly.Adhesive bond strength of 9.4MPa was obtained with Clearfil Photobond and that of 8.2MPa with our experimental bonding agent consisting of triethyleneglycol dimethacrylate(3G)/dl-camphorquinone(CQ)/1, 3, 5-trimethylbarbituric acid(TMB).