Based on rural household survey data in Taipusi County in Inner Mongolia Autonomous Region, this article analyzes agricultural land use intensity and its determinants. The results reveal marked differences of agricultural land use intensity among households with different ages of householders, proportion of non-farm participants, total agricultural land area, land fragmentation and land utilization capacity. (i) Households with older householders and households with a smaller proportion of non-farming laborers generally spend more time on managing their land and invest less capital and materials than other households. The proportion of non-farming laborers within younger households is relatively high, and they tend to invest more capital and materials because the income derived from non-farm employment relaxes their financial constraints, (ii) Land fragmentation is an important determinant of land use intensity. Households with a bigger land size per plot usually spend less time and invest more capital and materials on their land; (iii) Land with better quality is usually managed intensively. The results suggest that labor has become an important constraint for local agricultural production, and there is the potential to improve land management scale and increase machinery input to substitute for labor. Furthermore, the effects of non-farm employment on land use intensity indicate that the establishment of a coordination mechanism between non-farm employment and agricultural land use is an important way to solve the conflict between ecological security and agricultural production in ecologically-vulnerable areas.