In blend system of Phenolic resin (PF) and hyperbranched polyester (HBPE),PF phenolic hydroxyl group and HBPE terminal hydroxyl group occurs hydrogen bonding action, and the blends show single glass transition temperature, indicating better compatibility between the blends; adding HBPE can improve the impact strength of the cured PF and bending strength, when HBPE content is 15%, the impact strength is up to the maximum and improved over the original untreated by 145% , toughening effect is more obvious. Weihai CY Dendrimer Technology Co. Ltd forwards from “Hyperbranched Polyester modified phenolic resin’s preparation and curing properties study”  Songsong Wang 1, Dapeng Zhou 2 *,Li GU 2,Jian Li1,LiQiong Yu 3 (1 School of Materials Science and Engineering of Changzhou , Changzhou, Jiangsu 213164; 2 School of Biological and Chemical Engineering of Jiaxing, Jiaxing 314033; 3. Zhe Jiang Jiamin Plastic Co., Ltd., Jiaxing, Zhejiang 314027) China plastics, 2011,6 (25) :34-37