A high-performance capillary electrophoresis with amperometric detection (CE-AD) method has been developed for the determination of the pharmacologically active ingredients in different parts of Morus alba L. after a relatively simple extraction procedure. This method was also used in the comparison of bioactive constituent difference in the five parts, based on their electropherograms or characteristic "CE-AD profiles". The effects of several factors such as the acidity and concentration of running buffer, separation voltage, applied potential and injection time were investigated to find the optimum conditions. Method detection limits (S/N = 3) ranged from 1.5 x 10(-7) to 1.4 x 10(-8)g/mL for all 10 analytes, and the assay results were satisfactory.