Taking the lead-zinc mine basin in the village of Sidi of Yangshuo county, Guangxi as the research object, the content of Cr, Ni, Cu, Zn, As, Cd, Hg, and Pb in the surface soil of Sidi river were analyzed and determined. The Nemerow multi-factor index (NIPI) and comprehensive environmental capacity index (PI) were employed to evaluate the soil heavy metal pollution status and environmental capacity, and Empirical Bayesian Kriging spatial interpolation method based on ArcGIS software was employed to divide the ecological risk assessment and environmental capacity level of soil heavy metals in the watershed. The results showed that the average content of Mn, Cu, Zn, Cd, Sb, Hg, and Pb was 3.29-10.67 times higher than the environmental quality standards for soils in Guangxi, indicating that it has been differently enriched in topsoil. Zn, Cd, Hg, and Pb exceeded the standard seriously, with the exceeding rate ranging from 46.43% to 77.98%, indicating that it has greater risks to the environment and humans. The results of NIPI show that there is compound pollution in the study area, with 70% of the proportion of moderately polluted and severely polluted areas in different depth layers and the main controlling elements are Pb, Zn, and Cd. The results of the PI show that the range of PIs is -9.84~1.24, which is low environment capacity overall, and the main controlling elements are Cd, Hg, and Pb. The comprehensive evaluation shows that there is serious soil heavy metal pollution, low environmental capacity levels, and overall compound pollution in the study area. The degree of pollution showed a spatial distribution trend of gradually decreasing with increasing spatial distance from the Sidi River, while the opposite is true for environmental capacity. Compared with residential areas, the soil environmental capacity of agricultural activity areas is basically overloaded, and with greater environmental risks. Heavy metal pollution in agricultural activity areas is higher, which is more harmful to crops and indirectly endangers human health. The total environmental capacity of the study area has a trend of gradual improvement under the ideal condition based on the prediction results of environmental capacity in the last hundred years.