A method of providing location service for Wireless Local Area Network (WLAN) subscribers. With a location subsystem preset in the WLAN and the WLAN subscribers accessing to a 3G network the method comprises at least the steps of the WLAN location subsystem detecting whether it has received a location request from an LCS client in the 3G network if yes locating the target UE based on the received location request and returning the location result to the Gateway Mobile Location Center (GMLC) which will forward the location result to the LCS client; otherwise continuing to detect whether it receives the location request. The solution provided by the method makes it possible for LCS clients to apply via the 3G network the LCS in the WLAN inter-working with the 3G network.