Abstract: Aiming at the requirement of interoperability among subsystems owning different functions in the intelligent building, as well as the wide uses of LonWorks and BACnet standards in the building automation and control, and in order to solve the problem that a LonWorks networks which are composed of sensors and actuators will be added to a system using BACnet as the primary procotol, the new generation network service architecture LNS of LonWorks technology is introduced, and the C/S structure are put forward, and the mapping relationship and the method of realization in the gateway are expatiated. Finally, the development kits of driver programming of two technologies which gateway connects are depicted briefly, and the prospect of gateway application has been previewed.