PM_2.1 and PM₁₀ samples were synchronously collected at suburban and urban sites in Nanjing, 16 kinds of PAHs were analyzed by the GC-MS. The concentrations of total PAHs at the urban and suburban were in the ranges of 32.84~245.35ng/m³ and 21.43~225.72ng/m³ for PM₁₀, respectively, and 19.11~111.57ng/m³ and 19.69~125.21ng/m³ for PM_2.1. PAHs concentrations at the two sites were close to each other, and show similar seasonal variation with the winter concentrations larger than those in the summer. PAHs mainly compose of 4-, 5- and 6-ring PAHs that have mass fractions (to total PAH mass) of 78.7%~83.1% in PM₁₀ and 80.5%~87.1% in PM_2.1, and the fraction of 4-rings PAHs in winter was clearly larger than those of other seasons. The PAHs at two sites showed different diurnal variations. At the urban site, the concentration in the daytime was higher than that in the nighttime, whereas values in the nighttime become larger at the suburban site. Among the various meteorological parameters, the PAH concentration shows clearly negative correlations to both temperature and relative humidity, and a positive correlation is noticed between the PM₁₀ and PAHs. The influence of meteorological parameters was more significant in warm seasons (summer and autumn) than that in cold seasons (winter and spring). Ozone concentration also had a negative correlation to the 5- and 6-ring PAHs concentration. The results from air mass back-trajectory model show that the accumulation of PAHs was mainly influenced by local emission, and polluted airs from southwest and southeast of Nanjing are also an important source of the PAHs through shout-range transport.