A positioning system for obtaining information concerning a current position of a device even when one is in an underground center or inside a building includes a portable terminal is equipped with a radio-call-reception part having a radio-call-reception function that is a receiving unit which receives data sent from the base station and a positioning function to obtain the primary position data indicating the current position of the device based on data sent from the base station, a GPS-reception part having a positioning function to obtain the secondary position data on measuring the current position of the device based on signals sent from GPS satellites, and a position-data-correction function to correct the secondary position data using the position-correction data sent from the base station, and an information-processing part having a function to perform information processing using position data obtained from the radio-call-reception part and the GPS-reception part.