A simple system has been constructed for the quantitative determination of barley p-glucans. Measurements were made by the flow-injection-analysis (FIA) technique using the fluorescent dye Calcofluor as a specific reagent for (1-»3) (1-.4)-B-D-linkages. In this paper a single-line system is described involving only one pump samples of P-glucan being directly injected into the reagent stream. The reaction results in an increased intensity of fluoresc ence detected by a flow-through-cell fluorimeter and evaluated as peak heights or peak areas by a printer-plotter. The analysis is completed within 20s. The operational parameters were set during an optimization procedure.