The invention is directed to an RTK-GPS survey system. The survey system includes a server (9) in an IP-VPN communication network 10 for establishing communications between base stations (16 and 17) that transmit correction data and a rover station 15 that receives the correction data. Each satellite positioning device constituting a base station and a rover station includes at least a satellite positioning unit (11) that receives radio waves from artificial satellites, a communication unit (12) that performs a communication between the satellite positioning device, and a control unit (13) that controls the satellite positioning unit (11) and the communication unit (12). The control unit (13) of the rover station 15 can receive interference information registered in the control unit (13) of each satellite positioning device of the base stations (16 and 17), and select a base station that transmits most appropriate correction data among the plural base stations.