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It is of great importance to intuitively exhibit the spatial distribution characteristics of soil organic carbon density (SOCD) in range of 0~40cm soil depth and analyze the main influencing factors of organic SOCD. SOCD in dry farming region was calculated based on the sampling points obtained in 2017. The spatial threedimensional distribution characteristics of SOCD was simulated by inverse distance weighting method, and the influencing factors of SOCD was analyzed with the help of geographical weighted regression. The results showed that the SOCD in northeast was higher than that of southwest, and SOCD in different types of soil had large difference. Climate was the major influencing factor on SCOD in dry cropping areas. Moreover, climate and clay content had upward tendency to SOCD with the increase of soil depth. Annual average temperature had negative correlation with SOCD. It can be seen from the space that the regression coefficient was the highest in the northeast dry farming region of Heilongjiang Province, followed by Jilin and Liaoning Provinces in the central region of Heilongjiang Province and low in North China in all subregions, the regression coefficient of precipitation and SOCD was lower than 001, and the correlation was very small. The clay content was positively correlated with SOCD. The research results could provide effective support for estimating of organic carbon reserves and promoting carbon sequestration and emission reduction policies in the future.