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Heavy metal (loid) (HM) accumulation in the soil and the HM spatiotemporal distribution have important implication for soil pollution prevention and remediation.The present study investigated the concentrations and spatiotemporal distributions of lead (Pb),mercury (Hg),cadmium (Cd),chromium (Cr) and arsenic (As) in the topsoil of a coal chemical plant in Ningxia Autonomous region (Ningxia),China.Topsoil samples (n =153) were obtained using the checkerboard method,and the HM concentrations were determined.The soil residual rates of the five HMs were measured with leaching experiments and were applied in a soil environmental capacity model to predict the quantitative variation of the HM concentrations.The predicted results were employed to estimate the HM spatiotemporal distribution within 20 years with the Kriging technique.The number of sampling sites,where all five HM concentrations exceed their corresponding background values in Ningxia,would be increased from 0 to 90％ within 10 years of the plant operation.In addition,Pb and Cd were distributed along the traffic routes.Mercury and As were distributed near fuel gas emission vents.Chromium was mainly accumulated in slag dumps.The study may provide the theoretical and practical foundation for future HM pollution control in coal chemical plants.