A new automated assay specific for D-fructose has been devised, based on the chromophore produced by dehydration of D-fructose in hydrochloric acid. The chromophore had λ max at 470 (major) and 540 nm (minor). Carbohydrates not containing ketose residues do not interfere in the assay. The chromophore yields for sucrose, raffinose, and inulin were 96, 89, and 80%, respectively, of the yield from D-fructose. Advantages of the method include simplicity, inexpensive reagent, and non-interference of D-glucose. The assay was successfully applied to liquid samples taken from various stages in the industrial production of sugars.