A location server for providing a location information service to a target terminal comprising: an input interface adapted for receiving and transmitting messages (308, 312, 316) from/to a target terminal; a location server memory unit adapted for storing a message received through the input interface from the target terminal in response to a receipt by the terminal of an initial location service request message, the message including information of positioning methods for a triggered location request service that the target terminal supports; a location server message generator adapted for generating a request of a triggered location request service and various messages to be transmitted to the target terminal including a triggered location service response message with at least one positioning method that the location server supports; and a location server controller adapted for selecting the at least one positioning method. when the positioning methods included in said message are received from the target terminal, generating the triggered location service response message with the at least one positioning method, controlling to transmit the triggered location service response message to the target terminal through the input interface, receiving, from the target terminal, information with respect to a specific positioning method which is able to be used in a current electric wave environment of the target terminal and is selected from among the at least one positioning method included in the triggered location service response message, providing the location service during the triggered location request service using the specific positioning method when information for the specific positioning method is received from the target terminal, calculating a location of the target terminal according to the specific positioning method. an input interface adapted for receiving and transmitting messages (308, 312, 316) from/to a target terminal; a location server memory unit adapted for storing a message received through the input interface from the target terminal in response to a receipt by the terminal of an initial location service request message, the message including information of positioning methods for a triggered location request service that the target terminal supports; a location server message generator adapted for generating a request of a triggered location request service and various messages to be transmitted to the target terminal including a triggered location service response message with at least one positioning method that the location server supports; and a location server controller adapted for selecting the at least one positioning method. when the positioning methods included in said message are received from the target terminal, generating the triggered location service response message with the at least one positioning method, controlling to transmit the triggered location service response message to the target terminal through the input interface, receiving, from the target terminal, information with respect to a specific positioning method which is able to be used in a current electric wave environment of the target terminal and is selected from among the at least one positioning method included in the triggered location service response message, providing the location service during the triggered location request service using the specific positioning method when information for the specific positioning method is received from the target terminal, calculating a location of the target terminal according to the specific positioning method.