Hydroxyl acrylate emulsion was synthesized by seeded emulsion polymerization with butyl acrylate,methacrylic acid and hydroxyethyl methacrylate as monomers.The structure was characterized by infrared spectroscopy.The optimum conditions for the emulsion polymerization were that the reaction temperature was 75 ~ 85 ℃ and the amount of initiator was 0.3% of the mass of monomers.As the hydroxyl content increased,emulsion polymerization stability was decreased,gel content was increased,water resistance of the films was decreased,and hardness and adhesion of the films were improved.