Box-Behnken design experiments in response surface analysis were used to optimize the process conditions for the ethanol reflux extraction of total phenolic acid from Trollii Flos,and the scavenging ability of total phenolic acid from Trollii Flos on DPPH radicals and hydroxyl radicals and its inhibitory effect on tyrosinase were also studied.The results showed that the optimum extraction process of total phenolic acid from Trollii Flos was:ethanol concentration 60%,reflux time 90 min,reflux temperature 60 ℃,liquid to solid ratio 40∶1 (mL/g).The yield of total phenolic acid from Trollii Flos under these conditions was 92.245 mg/g.In addition,it had certain scavenging ability to DPPH radicals and hydroxyl radicals,and could significantly inhibit tyrosinase activity.The extract method is stable and reliable,and the total phenolic acid from Trollii Flos has certain in vitro antioxidant activity and tyrosinase inhibitory effect,which lays the foundation for further scientific and rational development and utilization of Trollii Flos.