Abstract: The pollution state of Atmospheric Aerosol and pollution characteristics of PAHs in Atmospheric Aerosol at the traffic crossing in city were studied. The samples of PM_2.5、PM₅、PM₁₀、PM_2.5～5.0、PM_5～10、PM_10～100 and total suspended particulates (TSP) were collected at one of the major traffic crossings, WuShiBei Road and ErHuang Road in Fuzhou. The concentration of mass PAHs in the various particle diameter aerosol were measured by the optimized high\|performance liquid chromatographic (HPLC) method with fluorescence programmed multiple wavelength shift detection. The results shown that the inhalable particulates (PM₁₀) in airborne particles were in the contribution of 70% to the total suspended particulates(TSP). 70% of inhalable particulates (PM₁₀) were PM₅; but the small diameter PM_2.5 were in percentage of 73% to PM₅. The PAHs raised by traffic pollution were mainly existed in the small diameter PM_2.5. According to the proportion of characteristics identified PAHs, it can been indicated that the main contribution to the PAHs production in airborne particles was from the dust raised by motor vehicles in traffic crossing.