A three-dimensional-information detecting system includes a switching portion that sequentially selects sensor coils of a three-dimensional-information detecting device. Electromagnetic coupling is used to perform signal transmission and reception between the sensor coils and input coils in input elements of a three-dimensional-information inputting device which are mutually perpendicularly provided. A signal received by a selected sensor coil is detected by a detecting portion. From the detected signal, three-dimensional information, such as the position and attitude of the three-dimensional-information inputting device, is calculated by a control unit.