A flow injection analysis (FIA) system capable of simultaneously determining the concentrations of starch and glucose in samples was set up. The system consisted of glucoamylase (GA), glucose oxidase (GOD), EC 1.1.3.4) and mutarotase (MUT, EC 5.1.3.3) immobilized on macroporous polymer packed in reaction cartridges was operated at 30-degrees-C. Glucose resulting from the action of glycoamylase or originally present in the samples was determined amperometrically. The starch was analysed with the system without needing prehydrolysis with alpha-amylase, and inclusion of mutarotase was found necessary only when the sample originally contained alpha-glucose. A linear detection range up to 1.5 g dm-3 and 4.0 g dm-3 was obtained for the streams from which glucose and total sugar concentrations were measured, respectively. The system was able to analyse up to 10 samples per hour.