Abstract: In order to screen lactic acid bacterias with excellent antioxidant activity, we conducted the preliminary screening based on the requirements of salt toleranced, high and low temperature resistance, high acid production and its tolerance for hydrogen peroxide. Then antioxidant activity of the strains was evaluated in vitro tests including anti-lipid peroxidation assay, hydroxyl radical assay and reducing powder evaluation experiment. A series of experiments show that 15 of selected strains of lactic acid bacterias complied with the requirements. And the antioxidant activity of seven strains was of significant difference. Moreover, L4, L11 and L21 strains demonstrated better capacity on antioxidant activity than the others. VITEK -2 automation microbe system and 16S rDNA sequence analysis show that the three strains were Pediococcus pentosaceu, Lactobacillus plantarum and L.casei.