In order to quantify the contribution of soil heavy metals in plateau mining areas, the surface soil of the study area is taken as the research object, and the positive definite matrix factor model (PMF) is used to analyze the sources of soil heavy metals. The average mass concentration of each element is lower than the soil pollution risk control standards for agricultural land. Among them, Hg, V, Cr, Cu, Zn, Cd, and Pb are 33.20, 1.41, 1.42, 2.83, 3.57, 2.96 and 1.48 times of Inner Mongolia soil background value . The accumulation of heavy metals in the soil is mainly affected by coal mining, fossil fuel combustion, and atmospheric traffic, and the relative contribution rates are 23.3%, 42.4%, and 34.3%, respectively. In addition, the combination of PMF model and geostatistical spatial analysis can further clarify the distribution of contribution sources, which is of practical significance for soil heavy metal pollution control in coal mining areas.