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In order to analyze the characteristics of heavy metal pollution in farmland soil of Chaohu Lake Basin, a village located in the west of Chaohu Lake was selected to collect soil samples in the field. The contents of heavy metals of Zn, Cr, Cd, Hg, Pb, As, Cu and Ni were determined by X-Ray fluorescence spectrometer. The pollution index method and potential ecological risk index method were used to evaluate the degree, spatial distribution and potential ecological risk of heavy metal pollution in soil. In order to further analyze the sources of soil heavy metal pollution, the sources of heavy metals were classified by principal component analysis and cluster analysis. Village DEM, railway buffer zone, village buffer zone, highway buffer zone, reservoir buffer zone and agricultural land classification were selected as variable factors to analyze their spatial correlation with the distribution of heavy metal pollution by using geographical detector. The results showed that a village was mainly polluted by Hg (Pi>17.2) and Cd (Pi>10.3). The main source of Pb, Cu, Zn and Ni was from the parent material of soilforming material. The source of Hg, Cr, Cd and As was mainly from the anthropogenic source of pollution. The type of agricultural land (PD,H=0.405) and railway distribution (PD,H=0.362) had the strongest explanatory power to the distribution of pollution. The pollution of Hg and Cd may come from cultivated land, livestock and poultry breeding land and railway. Sewage irrigation would also affect the spatial distribution of heavy metal pollution to some extent.