The decoctions of Pteris multifida have been applied to attenuate symptoms of benign prostatic hyperplasia (BPH) in folk medicine practice of Suzhou region in China.In this study, the total flavonoid extract (PME) of Pteris multifida was characterized at first.Phytochemical investigation of PME resulted in the isolation and identification of three flavones, apigenin-7-O-β-D-glucoside-4-O-α-L-rhanmoside (1), luteolin-7-O-β-D-glucoside (2) and apigenin-7-O-β-D-glucoside (3) on the basis of NMR spectroscopes.The contents of compounds 1-3 in PME were further determined by a HPLC-PDA method developed.Secondly, bioassay of PME against BPH was conducted in a testosterone-induced BPH in mice.After 4 weeks of administration, PME (180 mg/kg, i.g.) successfully decreased the prostate index in the mice.Histoarchitectural improvement in the prostate gland was also observed, accompany with the inhibition of the VEGF level and the activation of bFGF level in prostatic tissue.These results revealed that PME exhibit anti-BPH potential, which may be contributed to the applications of the herbal extract in treatments of BPH syndrome.