We studied vegetation productivity trends in Mongolia, using long-term remotely sensed vegetation index AVHRR NDVI (1982-2008). First, we related remotely sensed vegetation index NDVI long-term (1982-2008) average value intervals to main 6 ecological zones. Then we studied changes in areas within these NDVI intervals. Vegetation trends analysis in Mongolia, using long-term remotely sensed vegetation index NDVI (1982-2008) showed that main ecological zone boundaries didn’t shift. (1) Desert area didn’t change during last 27 years. (2) Averaged (2000-2008) area of southern part of the desert steppe expanded northward by 7.2% relative to average area between 1982-1990, however, northern part of the desert steppe shrunk by 4.7%. (3) Southern part of the dry steppe expanded northward by 6.5% and southern part of the dry steppe shrunk by 2.2% as comparison of average areas of sub-ecozones of the dry steppe between 2000-2008 and 1982-1990 showed. (4) The same comparison shows that mountain forest areas expanded by 11.1%, high mountain forest steppe reduced by 21.3%. However, there were changes within main ecological zones, particularly, southern drier parts with relatively lover productivity (southern sub-ecological zones) have expanded in areas by 6.5-11.1% northward, and the northern parts with relatively higher productivity (northern sub-ecological zones) have shrunk in areas. Expansion of southern sub-zones within ecological zones means that plant productivity tend to decrease due to climate and land use changes. This study was funded by the NASA and APN.