An extreme disaster of snow and cold took place at the beginning of 2008 and caused great damage to vegetation in South China.Taking Guangdong as an example,the authors analyze NDVI changes of damaged vegetation and healthy vegetation using MODIS data,extract distribution information of damaged vegetation through ISODATA algorithm of unsupervised classification method,and study the relationships between damaged vegetation and topography factors using 90 m SRTM DEM data.The results showed that vegetation in Guangdong was damaged seriously,with a damaged area reaching to 19 011.06 km²,and it was greatly affected by topography factors such as elevation,slope and aspect.Damaged vegetation mainly distributed in shady hillside with elevation higher than 400 m and slope less than 15°Through overlap analysis between IGBP vegetation map and damaged vegetation,it was found that damaged vegetation mainly covered the evergreen broadleaf forest,mixed forest,deciduous broadleaf forest,shrubbery,deciduous coniferous forest and evergreen coniferous forest.