Five biflavonoids were isolated and purified from the ethanol extract of Dysosma versipellis by silica gel column chromatography,Sephadex LH-20 column chromatography,and preparative HPLC.Their structures were identified as (+)-dysosmabiflavonoid H (1a),(-)-dysosmabiflavonoid H (1b),(+)-dysosmabiflavonoid I (2a),(-)-dysosmabiflavonoid I (2b),podoverine F (3) by extensive spectroscopic analysis (MS,UV,IR,NMR) and electronic circular dichroism（ECD） calculations.Compounds 1a and 1b,2a and 2b are two pairs of new biflavonoid enantiomers.Compounds 2,2a,and 2b showed significant DPPH scavenging capacity with IC₅₀ values of 8.87,10.18,11.35 μmol/L,respectively,in comparison with trolox (IC₅₀,14.95 μmol/L).Compounds 2,2a,and 2b displayed more potent DPPH radical scavenging activity than compounds 1,1a,1b,and trolox,respectively.The preliminary structure-activity relationship exhibited that the catechol hydroxyl group in B ring of flavonoids is essential for DPPH radical scavenging activity.