The present invention relates to a method for obtaining traffic information using the billing information of a mobile terminal. A specified number of a mobile terminal is obtained from billing information necessary for performing a billing operation when a telephone call is made using the mobile terminal on a highway (S61, S62 and S63). The moving time of the mobile terminal between base stations is tracked (S65), such that information of a traffic state on the highway can be obtained in real time (S66). The existing mobile communication network is employed to obtain the traffic information, such that the cost required for operating special vehicles for collecting traffic information and for obtaining traffic information from information providers can be reduced. Customer demand can be met as a measurement operations is continuously carried out and the traffic information abruptly changed is reflected in real time.