Various organic compounds form colored complexes with germanium. But nearly all of them are highly insoluble. Complex with phenylfluorone or hematoxylin, for example, which has been in practical use for the determination of germanium is difficultly soluble in water. The precipitate is, therefore, dispersed with gum arabic or gelatin. But growth or aggregation of the precipitates was observed on left standing and consequently transmittancy readings were changed with lapse of time. And thus reproducible results could hardly be obtained especially when concentration of germanium was high. Germanium complex with quercetin, on the other hand, is soluble. Accordingly satisfactory results were obtained. It obeied Beer\u27s law up to 0.54 γ/ml of germanium. Sensitivity is also enough