Envisat　Advanced　Synthetic　Aperture　Radar　(ASAR)　dual-polarization　data　are　shown　to　be　effective　for　regional　forest　monitoring.　To　this　scope,　an　automatic　SAR　image　preprocessing　procedure　was　developed　using　SRTM　DEM　and　Landsat　TM　image　for　geocoding　in　rugged　terrain　and　smooth　terrain　areas,　respectively.　An　object-oriented　forest　and　non-forest　classification　method　is　then　proposed　based　on　the　HH　to　HV　intensity　ratio　and　HV　images　of　ASAR　data　at　single　acquisition　in　winter.　The　developed　methods　were　applied　to　forest　and　non-forest　mapping　in　Northeast　China.　The　overall　accuracy,　the　user＇s　accuracy　and　the　producer＇s　accuracy　of　forest　are　83.7%,　85.6%　and　75.7%　respectively.　The　results　indicate　that　the　proposed　methods　are　promising　for　operational　forest　mapping　at　regional　scale.