Abstract:[Objective] Studying the relationship among slope & aspects, land use change and net primary productivity, so as to provide scientific basis for regional ecological sustainable development.[Methods] We took Baoji City as an example to study the effect of land use change on regional net primary production based on different slopes and aspects with the help of digital elevation model and the Landsat TM images. We used the CASA model to estimate net primary production of Baoji City.[Results] From 2000 to 2010, the change of net primary productivity in Baoji City was concentrated in forest land, cultivated land and grassland, among which forest land had the greatest influence. More than 96% of forest lands remained unchanged in the past ten years, and about 77% of grasslands was transformed into forest lands. The total area of forest lands was 12 239.67 km2. The net primary productivity of forest lands in the sloping land was the most significant, with a net increase of 166 668.60 g/(m2·a); and the net primary productivity increment in the semi-shady aspect area was the highest, reaching 182 230.00 g/(m2·a). The influence of cultivated land on the net primary productivity concentrated on the flat land and the gentle slope. The aspect's range is from the sunny aspect to the semi-shady aspect and the highest value was 59 479.5 g/(m2·a) at the sunny slope. The change of grassland was less affected by the aspect condition, so its effect on the net primary productivity was relatively balanced in the slope condition, and the slope distribution was mainly slope and gentle slope.[Conclusion] Overall, the ecosystem of Baoji City keeps a good situation. Moreover, keeping net primary production in sustained growth is very important, and to maintain the sustainable development of ecological environment, we should take better account of Baoji's location and terrain to make good use of the forest land in sloping land and the semi-shady aspect.