To remediate the heavy metals polluted soil around a closed smelter in Shaanxi Province, 15 soil profile samples were collected in the site and analyzed for heavy metals content, including Pb, Cd, Hg, As, Cu, Cr, Zn and Ni. The pollution situation was assessed by using the ecological hazard risk assessment method, and the contaminated soil was finally remediated by in-situ replacement engineering methods. The results showed that within top 0~20 cm soil layer, Zn contents ranged from 89.80 mg/kg to 724.03 mg/kg, Cu contents varied from 28.89 mg/kg to 1 271.81 mg/kg, Hg contents changed from 0.04 mg/kg to 4.48 mg/kg，and the Pb contents were around 48.69~12 021.15 mg/kg. Cd contents in the top soil layer of 0~120 cm were above the secondary standard value of soil environment quality, while Pb, Cd, Hg, Cu and Zn contents in soil within 0~120 cm were higher than those of the Lou soil background values. The results of potential ecological risk implicated that the potential ecological risk factor for Cd ranged from 26.0 to 21 118.6, and its slight, moderate, strong, very strong and extremely strong ecological hazards frequencies were 4.3%, 15.2%, 19.6%, 15.2% and 37%, respectively. The potential ecological risk factor of Pb ranged from 0.1 to 120.2, and its slight, moderate and strong ecological hazards frequencies were 93.5%, 4.3% and 2.2%, respectively. The potential ecological risk factor of Hg ranged from 0.1 to 83.4, and its slight, moderate and strong ecological hazards frequencies were 59.3%, 39.4% and 1.3%, respectively. Elements As, Ni, Zn and Cu, all had slight ecological hazards. The soil heavy metals pollution in the study area was mainly contributed by Cd, Pb and Hg. The in-situ replacement method was proved to be an efficient method for the smelter polluted soil remediation and it could achieve satisfactory performance.