A spectrophotometric method has been developed for the determination of chromium in waste water with 5-Br-PADAP (2-(5-brorno-2-pyridylazo)-5-diethylaminophenol). Chromium(III) forms a blue-purple complex at pH 4.7 upon heating. The color is very stable and is highly sensitive for chromium. At 600 nm it obeys Beer's law in the concentration range of 0–15μg of Cr(III) per 25 ml. The sensitivity and molar absorptivity of the reaction are 0.00065μg of Cr(III) per cm2 and 7.93×1041 · mole−1 · cm−1, respectively. The continuous variation and molar ratio methods indicate that chromium forms 1∶2 complex with the ligand.