The utility model discloses a can handle high load capacity heavy metal combined pollution's multistage elution system of uniting, it will wash the mixer, the conveyer, washing shale shaker and muddy water pond meet in proper order, hydraulic cyclone is connected in the muddy water pond, the inclined lamellar precipitation pond is connected to hydraulic cyclone's liquid outlet, hydraulic cyclone's bottom exit linkage chemistry elution pond, the exit linkage hydraulic cyclone in chemistry elution pond, the waste liquid collecting pit is connected to hydraulic cyclone's liquid outlet, hydraulic cyclone's bottom exit linkage washing pond, the waste liquid collecting pit is connected to the liquid outlet in washing pond, the bottom exit linkage filter press in washing pond, the bottom exit linkage inclined lamellar precipitation pond of waste liquid collecting pit, the bottom exit linkage filter press in clean water basin, inclined lamellar precipitation pond is connected in the inclined lamellar precipitation pond. The utility model discloses a physics separation technology and chemical elution technique are united mutually, can be on a large scale high -efficiently realize economically that high load capacity heavy metal contaminated soil's subtracts appearance, decrement processing and utilization.