Abstract: Considering the Renshou region in the Sichuan province as an example，authors showed the process and effect of the operation of such a system. Using forest fire danger index instruments to monitor forest fire risk grades in real time，a real time forest fire warning system was designed using ArcGIS Engine10 as the platform and using SQL Server 2005 as the database.The proposed system consists of three processes：selecting the appropriate locations to install the forest fire danger index instruments，calculating the fire danger index and fire risk grade， and plotting thematic maps and information issues.Owing to such a system，fire risk grades and their spatial distribution can be displayed on electronic maps and datasheets.The proposed system was tested in Renshou region in the Sichuan province，and the results showed that the forest fire warning system can predict forest fire risks rapidly and in real time;thus allowing us to adopt preventative or protective measures against potential fires.

Key words: GIS secondary development, Fire risk grade forecast, Forest fuel, Fire risk index