A previously established mobile phase composition for a high-performance liquid chromatography (HPLC)-electrochemical detection (ED) method for the determination of Brazilein is further examined by HPLC-UV. Each component in the mobile phase is evaluated by the HPLC-UV system, and a convenient HPLC-UV method for the determination of Brazilein is developed. The mobile phase of this HPLC-UV method consists of sodium dihydrogen phosphate (NaH(2)PO(4)). The detection limit of Brazilein (signal-to-noise = 3) is 1 ng, and the calibration graph of Brazilein ranges from 1-120 ng per 20-microL injection. The validity of the proposed HPLC-UV method is demonstrated by the analysis of Brazilein in real plant samples. The differences between the HPLC-ED method and the proposed HPLC-UV method are given.