Abstract: The article combined the positive matrix factor decomposition (PMF) model and health risk assessment model to construct a quantitative source analysis method for the health risk of polycyclic aromatic hydrocarbons (PAHs). And taking urban and rural soils in Taiyuan as an example, we quantified the carcinogenic risk of each source based on total risk assessment and quantitative source analysis of concentrations, and then compared the differences of different sources on soil PAHs concentration and contribution to carcinogenic risk, emphasizing the importance of quantitative risk source analysis.. The importance of quantitative risk source analysis was emphasized. The results showed that the PAHs contamination in Taiyuan soil was serious, and the carcinogenic risk of soil PAHS exposure exceeded the acceptable risk level (10^-6) for the population in urban areas, and the probability of exceeding the acceptable threshold for the population in rural areas ranged from 10-50%. PAHs in urban soils are mainly from coal-fired traffic mixed sources, coal combustion, petroleum sources, coke oven emissions and traffic emissions, and PAHs in rural soils are mainly from coal combustion, biomass combustion, traffic emissions and coke oven emissions. The contribution of different sources to the concentration of PAHs and their contribution to carcinogenic risk differed. For urban areas, the contribution of mixed coal-fired traffic sources and coal-fired sources to the concentration of PAHs was 41.5% and 26.0%, respectively, while their contribution to the carcinogenic risk was 53.7% and 15.1%, respectively. For rural areas, traffic sources contributed 22.7% to the concentration but constituted 46.3% of the carcinogenic risk; biomass combustion sources accounted for 22.3% of the total source concentration but only 5.8% of the total source risk. Therefore, traffic source avoidance is the key to reduce the carcinogenic risk of PAHs. It is suggested that the quantitative source analysis technique based on health risk should be applied to soil risk control in order to reduce health risk more effectively and protect human health.