Abstract: Epoxy itaconate resin(IE) was synthesized by esterification of itaconic acid(IA) with epoxy resin E51. The IE was then reacted with different half-terminated isocyanates to prepare epoxy itaconate resin modified with isocyanate(DIHIE) in order to improve the UV curing activity. In next, the chemical structure and particle size distribution of IE and DIHIE were characterized by FT-IR, ¹H NMR and laser particle sizer. The results showed when the molar ratio of carboxyl group to epoxy group was 2∶KG-*91, the reaction temperature and time was 90 ℃ for 4 h, and the amount of catalyst N, N-dimethylbenzylamine was 3% of the total amount of reactants, while the conversion rate of the IA was about 95%. The half-terminated isocyanate intermediate was synthesized from isophorone diisocyanate(IPDI) and hydroxyethyl methacrylate(HEMA), and then it reacted with IE to obtain IPDIHIE. IPDIHIE was synthesized with acetone as solvent, which was carried out at acetone reflux temperature(56 ℃) for 8 h. The storage stability of the DIHIE dispersion was better when triethanolamine(TEOA) was used as neutralizing agent. The UV curing activity of the resins were improved obviously after being modified by half-terminated isocyanate. The curing time was shortened from 100 s to less than 60 s after modification. The pencil hardness of paint film could reach 4H and the adhesion performance was excellent. Moreover, all of them were about 1 grade.