Abstract: Concentrations of polycyclic aromatic hydrocarbons(PAHs) in gas phase and particle phase were determinated by GC/MS, and seasonal gas-particle partitioning of PAHs was examined by correlating the partitioning coefficient(K_P) with the sub-cooled vapor pressures(P_L). Results show that concentrations of PAHs in gas phase are higher than that in particle, and the variation in slopes according to air mass origin is insignificant for summer and winter samples, which indicate that meteorological condition may play an important role in the partitioning of PAHs.