Abstract: The compilation of greenhouse gas (GHG) inventory is a basic work for reducing GHS emissions. The GHS inventory involves many fields such as energy, agriculture, land use change, forestry, waste management, various industrial processes and electric power transfer. Therefore it is much professional, with complex calculation and many valuation models; the determination of parameters is difficult and needs large amount of data. The support of modern information system technology is thus required. The Web GIS technology was introduced into the GHS inventory compilation. Using the SQL SERVER as the backend database, calling the interface of the Google Maps and adopting key technologies such as AJAX and .net, networking of data transmission and management, automation of computation and assessment, professionalization of statistical analysis and structuration of data storage and management were realized. The test and application show that the system has friendly interface and perfect functions and can be simply operated. It can serve either as an auxiliary tool of GHS control by professional organizations, or as the sharing network platform for the governments to manage reduction of GHG emissions.