Abstract: Tangxun Lake is the largest urban lake in China, which is greatly affected by human activities. In order to investigate the pollution status of polycyclic aromatic hydrocarbons (PAHs) in Tangxun Lake, a total of 23 surface sediment samples were collected in August 2020, and the contents of 16 PAHs were detected by GC-MS. The results showed that the concentration of PAHs in the surface sediments from Tangxun Lake ranged from 219.13 to 3917.36 ng·g^-1, with a mean of 715.58±809.80 ng·g^-1, the pollution degree of the outer lake was higher than that of the inner lake. The PAHs concentrations were significantly positively correlated with the total organic carbon (TOC) content in sediment, and the correlation between TOC and high molecular weight PAHs was more significant.The 4-6 rings PAHs were the main components in the surface sediment, accounting for 78.05% of the total PAHs, and Fla, Phe, Pyr, BghiP and Chr were the highest components. Compared with other domestic lakes, the PAHs pollution of Tongxun Lake was at a medium level. PAHs source analysis were carried out by a isomerratio method and principal component analysis and multiple linear regression (PCA-MLR), and the results showed that the PAHs were mainly originated from combustion sources (petroleum combustion, coal combustion and biomass combustion), and a small part of PAHs came from petroleum product leakage. The contribution ratio of traffic emission sources were 62.62%, and the contribution ratio of mixed sources of coal and natural gas combustion and oil leakage were 37.38%.The results of sediment quality standards(SQSs) showed that the overall level of ecological risk of PAHs in sediments of Tangxun lake was relatively low, and there were some areas with medium risk. The relevant departments should strengthen monitoring and treatment of the medium polluted areas.