In order to understand land use/land cover changes (LUCC) and the eco-environment response to LUCC in farming-pastoral zone of the northern China during the recent twenty years, Baotou prefecture was selected as a case study area for investigation and quantitative evaluation. Technologies of remote sensing (RS), global positioning system (GPS), geographic information system (GIS), and other statistical methods were employed to implement. Results showed that: (1) During the recent twenty years, the areas of forest lands, grasslands and water were reduced, whereas the areas of other types were enlarged. Parts of forest lands, grasslands, and waters had become farmlands, and about 31.5% of the changed grasslands transferred into unused lands. The newly increased farmlands mainly came from grasslands and unused lands. And the newly increased construction lands mainly came from grasslands and farmlands. (2) Regional eco-environmental quality decreased by 12.6%, for which the land degradation (especially the meadow degeneration) and the developing of the cultivated land were mainly responsible, and their contributions to the regional eco-environment changes were 51.84 and 23.63% respectively. (3) The tendency of LUCC and the coo-environment response to LUCC displayed spatial heterogeneity. It can be concluded that the present agricultural production mode was not sustainable in farming-pastoral zone of northern China. Land degradation, especially meadow degradation induced by over-trarnpling and overgrazing, and developing of cultivated land were mainly responsible for regional eco-environment deterioration. Changing the cultivated land to forest or grass, however, can relieve deterioration of local coo-environment to some extents. And in the farming-pastoral zone in the northern China, evaluating regional coo-environment responses to LUCC was very necessary due to its fragile coo-environments.