The present invention relates to a ground coil device for magnetic levitation railway which can be manufactured with a high productivity and exhibit a less fluctuation in strength, a reduced weight and a good recyclability, and a process for manufacturing the device. There are provided a ground coil device for magnetic levitation railway which includes a coil conductor covered with a thermoplastic resin molding material containing (A) 100 parts by mass of a thermoplastic resin, (B) from 20 to 200 parts by mass of an inorganic filler, and (C) from 0 to 25 parts by mass of an elastomer, and a process for producing the ground coil device for magnetic levitation railway which includes the step of filling the thermoplastic resin molding material into a cavity of a metal mold into which the coil conductor is previously inserted, by an injection molding method, to obtain an integrally molded product.