Abstract: The atmospheric particulates in typical areas in Tianjin were measured.58 kinds of PAHs are determined and 11 kinds of them were analyzed quantitatively . The result showed that benzo(a) pyrene concentration was mostly above the national ambient air quality standard during the heating season , with the exceeding rate of 1.1～4.6. The pollution level in heavy traffic areas was higher than that in other areas . The distribution of PAHs on various diameters of atmospheric particulates ,and the correlation between benzo (a)pyrene and TSP or the other PAHs were analyzed and assessed.