An analytical system was developed which allows the determination of individual inorganic sulfur species in mixtures containing any combination of sulfide, sulfite, thiosulfate, sulfate, trithionate, tetrathionate, pentathionate, and hexathionate. The procedure employs high speed ion-exchange chromatography to separate the sulfur anions. The column effluent undergoes continuous analysis using in-stream oxidation with bromine and the resulting sulfate is measured spectrophotometrically after addition of iron(III)perchlorate to the effluent stream. This detection method provides several advantages over more common ultraviolet detection techniques. Sulfate is detectable even though it does not have significant absorption either in the visible or ultraviolet range. Ultraviolet absorbing materials containing no sulfur do not readily interfere since the measuring wavelength is 335 nm. The sensitivity of the detector is proportional to the number of sulfur atoms present in an anion, allowing better detection of polythionates, especially trithionate, and easier quantification of individual species.