In this paper, a HPLC method was developed for the determination of alkaloids in Sophora flavescens Ait. Experimental evidences indicate that a system of a LiChrosorb-NH2 column (4.0 mm x 250 mm) as stationary phase and CH3CN--H3PO4(pH2)--CH3CH2OH(80:8:10) as mobile phase can separate the five alkaloids, sophocarpine, matrine, sophoridine, oxysophcarpine and oxymatrine very well. This method is very easy and efficient and takes only 15 min for one run.