Abstract:The ultrasonic-assisted synchronous extraction conditions of tea polyphenols（TPP）and tea polysac－ charides （TPS）from Huaguoshan Yunwu tea and antioxidant activities of the extracts were investigated. On the basis of single factor experiments， Box-Behnken design and response surface methodology were applied to opti－ mize the extraction conditions. The optimal extraction conditions were as follows： ultrasonic power 500 W， ex－ traction temperature 80 ℃， extraction time 37 min， liquid to material ratio 62∶1（mL/g）. According to the opti－ mal process conditions， the yield of TPP and TPS were（137.08±3.37） mg/g and（57.71±1.94） mg/g dry basis. The yield of solid ultrasonic-assisted extracts （UAE） was （2.51±0.27） %， the contents of TPP and TPS were （548.31±13.48）mg/g and （227.28±6.44）mg/g UAE respectively. The antioxidative activities of UAE were es－ timated by measuring reducing power and total antioxidant capacity， the scavenging activities on DPPH free radical， hydroxyl free radical and superoxide anion free radical. The results indicated that UAE had the strong reducing power and total antioxidant capability， as well as the high eliminating activities on DPPH free radical， hydroxyl free radical and superoxide anion free radical.