Abstract: In this paper,the effects of ultrasonic time,ultrasonic temperature,pH and enzyme addition on the hydrolysis rate of fatty acid were investigated by single factor test. The lipase hydrolysis conditions of safflower seed oil assisted by ultrasonic were optimized by the response surface test. The changes of kinetic parameters Km and apparent kinetics in ultrasonic assisted enzymatic hydrolysis and water bath hydrolysis were compared.The optimized parameters were as follows:ultrasonic time 10 h,ultrasonic temperature 35℃,pH7.0,enzyme dosage of 220 U/g,water/oil ratio of 1.6:1.Under this condition,the hydrolysis rate was 94.47%.In addition,the apparent kinetic parameters Km and Ea of safflower seed oil hydrolysis assisted by ultrasound were respectively measured as 4.63 mL/g and 2.05 kJ/mol,which were less than those of controlled trial 14.93 mL/g and 2.40 kJ/mol and suggested that ultrasonic could facilitate the lipase hydrolysis of safflower seed oil.