Circuit substrate device and circuit substrate module device

Provided a circuit substrate device on which printed wiring substrates (11, 12) are electrically connected to each other by using an anisotropic conductive member (15) arranged between the printed wiring substrates (11, 12). The anisotropic conductive material (15) includes: an insulating elastic resin material (16); a metal fine lines (17) having an intermediate portion embedded in an insulating elastic resin material (16) so as to connect connection terminals (13, 14) corresponding to the printed wiring substrates (11, 12); and a resin layer (18) having a bending rigidity greater than the insulating elastic resin material (16). The printed wiring substrates (11, 12) and the anisotropic conductive material (15) are formed into an assembly having a curved surface. The resin layer (18) is a shape-keeping resin which keeps the curvature of the respective main surfaces of the anisotropic conductive member (15) matched with the curvature of the printed wiring substrates (11, 12).