A simple, rapid and sensitive spectrophotometric method has been developed for the determination of trace amounts of selenium in water samples, soil, plant materials and human hair. The proposed method is based on the reaction of selenium with potassium iodide in acidic medium to liberate iodine. The liberated iodine bleaches the Violet colour of azure 13, which is measured at 644 nm. This decrease ill absorbance is directly proportional to selenium concentration. Beer's Law was obeyed in the range 2.0-10.0 mu gmL(-1) of selenium. The molar absorptivity, Sandell's sensitivity, quantitation limit and detection limit of the method were found to be 0.9473 x 10(-5) L mol(-1) cm(-1), 8.33 x 10(-4) mu g cm(-2), 0.070 mu gmL(-1) and 0.023 mu gmL(-1). respectively. The proposed method has been successfully applied to the determination of selenium in various samples.