The optimization of the flavonoids extraction technique of Coreopsis tinctoria Nutt tea and the vitro antioxidant activity of flavonoids was studied by taking the Coreopsis tinctoria Nutt tea as the raw material, and basing the single factor experiment and Box-Behnken methodology. Results:The optimal extraction conditions of flavonoids from Coreopsis tinctoria Nutt tea were: extraction time 13 min, extraction temperature 98 ℃, the ratio of solid to liquid 1∶78 (g/mL). Under the conditions, the flavonoids extraction rate was (20.39±0.07)%. The half inhibiting concentrations (IC₅₀) to FRAP and DPPH free radical scavenging were (137.98±1.56) μg/mL and (82.40±1.98) μg/mL, respectively. The ORAC value was 1 427.89 μmol TE/g·DW, which indicated that the flavonoids from Coreopsis tinctoria Nutt tea exhibited significant antioxidant activities in vitro.