Abstract: Based on the 1:250 000 land quality geochemical survey data of the main cultivated lands in eastern Oroqen Qi, Inner Mongolia, the paper ascertains the organic carbon storage in surface and deep soils and distribution characteristics of organic carbon density in the study area, analyzes the relation of soil organic carbon storage and density to soil type and land use pattern, and discusses the effect mechanism of soil type and land use pattern on soil organic carbon. The results show that the soil organic carbon is unevenly distributed, with soil type and land use pattern as the main factors affecting soil organic carbon storage and density.