OBJECTIVE To establish a HPLC method for the determination of feulic acid,psoralen and isopsoralen in Jiegu capsule. METHODS The samples were extracted with chloroform by ultrasonic agitation and determined by HPLC using methanol water glacial acetic acid(40∶60) as the mobile phase with UV detection at 330 nm. RESULTS The method was linear over the ragne of 0.25～8.0μg·mL^-1(r＝0.9999) for ferulic acid,0.75～12.0 μg·mL^-1(r=0.9998) for psoralen and 1.0～16.0μg·mL^-1(r=0.9997) for isopsoralen,respectively.The average recoveries were 96.6%,101.1% and 99.62% with 0.86%,0.93% and 0.74% of RSD (n=5),respectively. CONCLUSION The HPLC method was sensitive,simple and accurate.