To provide an organic semiconductor circuit substrate capable of simplifying a manufacturing method.

This organic semiconductor circuit substrate 1 is formed by mounting an organic transistor 2, an organic diode 3 and a thin-film capacitor 4 on a substrate 5. The organic transistor 2 is formed by stacking a gate electrode 6, a gate insulation layer 7, a semiconductor layer 8 and source-drain electrodes 9 and 10. The organic diode 3 is formed by stacking a positive electrode 11, a semiconductor layer 12 and a negative electrode 13. The thin-film capacitor 4 is formed by stacking a positive electrode 14, a dielectric layer 15 and a negative electrode 16. The gate insulation layer 7 of the organic transistor 2 and the dielectric layer 15 of the thin-film capacitor 4 are formed of the same dielectric material 17 selected from tantalum pentoxide, titanium dioxide, aluminum trioxide, barium titanate, and barium-strontium titanate. The semiconductor layer 8 of the organic transistor 2 and the semiconductor layer 12 of the organic diode 3 are formed of the same organic semiconductor material 18.