Abstract: The properties of modified product of acrylic phenolic resin containing quaternary ammonium salt groups (APRQA),and the effect of chemical modification on solubility,thermal property,and photo-crosslinking property,were studied in this paper. The experiment results showed that the modified resin exhibits much lower decomposition temperature and has good solubility in water,ethanol,DMSO,and DMF. After 30?min,thermocured at 160℃,the product of modified resin becomes insoluble in water. The photo-crosslinked film of modified resin has good physical properties as that of APRQA