Abstract: With the advancement of the global sustainable development process, more scholars have paid attention to the way of studying spatial and temporal accumulation of environmental pollutants through science and technology. Research on PAHs mostly focuses on the estimation of pollution on a large spatial scale, and few studies on accurate analysis of special areas. However, different regions have unique geographical ecological environment and pollution factors, resulting in different main pollution compounds of PAHs in different polluted areas, and it is necessary to conduct targeted research on the pollution status of PAHs. In this paper, a total of 20 topsoil samples were collected from a power plant in Shanxi Province, and the characteristics of PAHs pollution and their impact on ecological security were investigated by means of isomer ratio method, Bap toxicity equivalent factor method and Maliszewska-Kordybach pollution classification criteria. The results showed that the average content of ∑₁₆PAHs in the study area was 1016.17㎍/kg, and the average content of ∑₇PAHs was 1614.71㎍/kg, and the average content of ∑₇PAHs accounted for 55.59% of the total content of ∑₁₆PAHs. Flu, BghiP and InP are the main PAHs that cause pollution within 0-500m, 500m-10km and 10-20km of the power plant. The content of polymer ring PAHs is the highest, and the main sources of PAHs are biomass combustion and coal combustion. Seven kinds of carcinogenic PAHs accounted for 98.93% of the total Σ₁₆TEQ (Bap), and the carcinogenic BaP compounds contributed the most to the toxicity of the study area, accounting for 80.19% of the total Σ₁₀TEQ (Bap). The heavily polluted area of PAHs is located within 500m upwind and 10km downwind of the power plant, the moderately polluted area is located within 10km upwind and 20km downwind, and the area deviating from the wind direction produces slight pollution or no pollution. The results of this study indicate that the comprehensive consideration of the soil conditions of the polluted areas can obtain more accurate zoning of major PAHs pollution compounds and pollution degree, which is of great significance for the detailed analysis and accurate control of PAHs point source pollution.