Obtaining and locating method, locating service device and system of subdistrict position

The invention provides an obtaining and locating method, a locating service device and a system of subdistrict position, belonging to the mobile communicating field. The obtaining method comprises the following steps: the locating service device receives a locating request carrying the identification of the subdistrict in which a first terminal is located from the first terminal; the judgment result is generated after the locating service device judges whether the subdistrict position information corresponding to the subdistrict identification is stored into the base station database of the locating service device; if the judgement result is yes, the locating service device transmits a first locating request to the first terminal; the locating service device receives the first position information from the first terminal, and the first position information is a returned position information after location is implemented by the first terminal according to the first locating request; the locating service device takes the first position information as the subdistrict position information corresponding to the subdistrict identification to store. The invention can be used for locating subdistrict position of the terminal in a roaming state.