Objective To study extraction of flavonids in hemerocallis citrina baroni and its medical effects. Methods Flavonids was isolated by Soxhlet extracted method with ethanol ,and purificated by absorbent with Polymide column and eluted with hot ethanol. Results Scavenge rate to OH· with the HCBF were 38.7%. The killing rates of Staphylocaccus aureus, Escherichia coli and Candida albicans for 30 min at 37℃ were 30.25%,48.12% and 61.22% ,respectively; and its germicidal efficacy increased with containing. Conclusion The HCBF was...