This study aims to investigate the pollution level and source of polycyclic aromatic hydrocarbons(PAHs) in the soil around a centralized drinking water source in Wangcheng district of Changsha, Hunan, China. The 0-20 cm soil in the first and second protection areas of the water source was taken as the research object. In 2018, three(1#-3#) and twelve(4#-15#) soil sampling points were arranged in the first and second protection areas respectively by the grid method, and 11#-15# soil sampling points were arranged in 2014. Fifteen varieties of PAHs including acenaphthene(Ace), acenaphthylene(Acy), anthracene(Ant), phenanthrene(Phe), fluorine(Flu), benzo[a] anthracene(BaA), pyrene(Pyr), chrysene(Chr), fluoranthene (Fla), benzo[a]pyrene(BaP), benzo[b]fluoranthene(BbF), dibenzo[a,h] anthracene(DBA), benzo[g,h,i]perylene(BghiP) and indeno[1,2,3-c,d]pyrene(IcdP) were taken into account. The risk assessment was carried out with the model of toxic equivalent concentration and incremental lifetime cancer risk. Results showed that the contents of 15 PAHs in the soil of the protected area were 75.22-617.86 ng/g with the average of 670.96 ng/g. Among which, the contents of 7 carcinogenic PAHs(BaA, Chr, BbF, BkF, BaP, DBA, IcdP) ranged from 12.13 to 2 989.26 ng/g with the mean of 319.80 ng/g. The soil samples 2# and 4# were moderately contaminated with PAHs, while sample 12# was heavily contaminated, and other samples were mildly contaminated or uncontaminated. Fla, Pyr and Phe were the main pollution factors. The PAHs content in the soil of the first-level protection area was lower than that of the second-level protection area. Apart from 12# sampling point, the PAHs ratio of 3-ring and 4-ring in the soil of the other point samples was more than 60%. Application of the characteristic ratio method to analyze the source of pollutants showed that the PAHs in the first-level protected area of the water source mainly came from the mixed pollution of petroleum and combustion sources, affected by the regional transportation factors and the migration and settlement of PAHs from upstream industrial and domestic waste. PAHs in the soil of the secondary protection area were mainly from the mixed pollution of petroleum combustion and biomass and coal combustion, related to human activities and traffic factors in the region. The results of health risk assessment indicated that the total cancer risk values of PAHs in the first- and second-level protected areas of water sources were between 10-6 and 10-4, indicating potential health risk.