Abstract: Objective: To explore the antioxidant activity of Selaginella pulvinata ( Hook, et Grev.) Maxim of total flavone and its growth inhibitory effect on He Lla、PC-3 M and MDA-MB231 cells. Methods: Fenton reaction, pyrogallol auto-oxidation and DPPH radical-scavenging systems were used for antioxidant evaluation of total flavonoids in vitro. The reducing power was evaluated by potassium ferricyanide assay.Growth inhibitory effect of total flavonoids on Hela, PC-3 M and MDA-MB231 cells was assessed by CCK-8 assay. Results: The scavenging effects of the total flavonoids on the hydroxyl, superoxide anion and DPPH free radicals increased as the total flavonoids concentration increased within 20¹00 μg/m L.The EC₅₀ of total flavonoids in scavenging hydroxyl, superoxide anion and DPPH free radicals were 111.86, 89.24, 26.51 μg/m L, respectively.The growth of He La, PC-3 M and MDA-MB231 cells was remarkably inhibited by total flavonoids in a dose-dependent manner within the conservation of total flavonoids of 6.59⁷9.02 μg/m L.The inhibiting Hela, PC-3 m and MDA-MB231 cells growth in 72 h was higher than in 48 h. Conclusion: Total flavonoids of Selaginella pulvinata ( Hook, et Grev.) Maxim shows strong antioxidant activity and good inhibitory effect against the growth of Hela, PC-3 m and MDA-MB231 cells.