After the relocation of a steel plant, 191 sampling holes were set in the main plant, using the layering (5 layers) sampling of 0-5 m soil, the concentration of polycyclic aromatic hydrocarbon compounds (PAHs) in soil was analyzed. The stratification of the concentration of five PAHs pollutants including benzo (a) anthracene, benzo (b) fluoranthene, benzo (a) pyrene, dibenzo (a,h) anthracene and indene (1,2,3-cd) pyrene was studied, the Nemerow index (P) used to evaluate the degree of pollution, and the RBCA Version 2.5 model applied to assess cancer risk. The results showed that the average concentration of the five pollutants in the first, second and the third layers of the soil was higher than the screening value of the residential land in the Site Soil Environmental Risk Assessment Screening Value (DB11/T 811-2011). The average concentrations of other pollutants were lower than the screening values of residential land except for benzo (b) fluoranthene, benzo (a) pyrene and dibenzo (a,h) anthracene in the fourth layer, dibenzo (a,h) anthracene in the fifth layer. The Nemerow index (P) which reflected the pollution of soil PAHs gradually decreased from the topsoil, with P of benzo(a) anthracene falling from 69.75 to 1.99, P of benzo(b) fluoranthene decreasing from 84.75 to 3.12, P of benzo(a) pyrene dropping from 163.75 to 5.68, P of indene(1,2,3-cd) pyrene decreasing from 111.92 to 0.91, P of dibenzo(a,h) anthracene decreased from 393.20 to 3.21, which indicated that the degree of soil PAHs pollution was gradually decreasing. Among the five PAH compounds, benzo(a) pyrene as single pollutant contributed the highest to carcinogenic risk, being up to 56.11%, with the main exposure pathway of oral intake. This factory area must be treated and meet administrative standard before using as residential land.