[Objective] This study analyzed the pollution characteristics and sources of polycyclic aromatic hydrocarbons(PAHs) in farmland soil from Xiaodian sewage irrigation area in Taiyuan City. The results should facilitate the development of farmland environment evaluation and soil pollution prevention strategy in the study area.[Methods] 15 surface soil samples were collected, and their concentrations and composition of 16 PAHs listed for prior control by US EPA were detected with a gas chromatography equipped with mass spectrometry (GC/MS). The sources and ecological risks of the soils were assessed.[Results] The results showed that 16 PAHs were generally detected, with the detection ratio of 100%. The total PAHs concentrations varied from 0.315 to 7.661 μg/g, with an average value of 3.568 μg/g. In terms of composition, the contents of PAHs of 2, 3 rings accounted for 64.2% of the total PAHs, the contents of PAHs of 4 rings accounted for 14.2%, and the percentage of 5, 6 ring-PAHs was 21.6%. Thus, the contents of PAHs with low and middle rings were much higher. Based on ratio method and in-site investigation, it was induced that the PAHs sources were not only related with water quality and history of sewage irrigation, but also with the sources from the combustions of wood, coal and fossil fuels.[Conclusion] Compared with the relative research of farmland soils at home and abroad, PAHs pollution in this area was in medium or higher level. According to the standards recommended by Maliszewska-Kordybach, the total concentrations of PAHs exceeded the limited value in all the sampling points. However, these values were below the "National Environmental quality standards for soils(GB15618-2008)" proposed by China.