Abstract: In order to reveal the spatial variation of soil organic matter and its influencing factors in the arable layer (0~20cm) in mountain areas of Northwestern Hubei Province, Shiyan City was used as the study area to analyze the spatial variation of SOM based on geostatistical methods. And we used Geodetector to explore the influencing factors of the spatial variation of SOM and their interactions. The results showed that the average content of SOM was 17.48 g/kg, which was in a deficient state; the coefficient of variation was 45.59%, which was a medium variation intensity; the Nugget coefficient was 0.496, which was moderate autocorrelation; the anisotropy of the spatial autocorrelation was significant, with the most significant variation in the 45° direction. SOM showed a decreasing trend with decreasing elevation. Annual precipitation, cropping system and elevation were the strongest explanatory and dominant factors determining the spatial distribution pattern of SOM in Shiyan City, while the explanation of parent materials and land use was relatively weak. Two different kinds of factors showed the function of nonlinear enhancement or double factor enhancement. The spatial variability of SOM was the results of the combination of all the factors, which showed the diversity and complexity of the influencing factors of the spatial heterogeneity of SOM in the arable layer. The results can provide theoretical basis for precise management of SOM, improvement of soil quality, and promotion of agricultural production in the study area.