Abstract: Forest thematic mapping was of high cost work. But now we can promote the efficiency greatly with the combination of remote sensing and computer technology. The 1∶20?000 colour infrared photograph in Zijing mountain area of 1996 was enhanced with many methods. It was shown that forest information could be most extracted using NDVI and KL transformation. Furthermore, the forest types were classified automatically by combining non-supervised and supervised methods, and the classification accuracy reached 87.4%.Finally,the forest type map was output. So we can make a map of new forest types rapidly, gain some help to manage this landscape area well using the modern mapping method.