Previous studies on the Khat plant (Catha edulis, Celastraceae) illustrated the importance of using freshly harvested young shoots and leaves such that cathinone, the principle active component and Schedule I controlled drug contained within the plant, could be suitably isolated and identified. The purpose of this work was to develop a quantitative analytical technique for the determination of cathinone. The proposed method is based on treating the reductant cathinone with copper(II)-neocuproine reagent in sodium acetate-buffered medium followed by measuring the absorbance of the copper(I)-neocuproine complex at 455 nm. The calibration plot is linear in the range 0.08-25 micrograms ml-1 with a detection limit of 0.08 microgram ml-1. The precision of the method, expressed as the relative standard deviation, is 1.35% for 10 micrograms ml-1 cathinone. Good recoveries have been obtained in applying the method to the analysis of cathinone in Khat leaves.