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The pollution level and spatial distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) in snowfall of typical city of the alpine region of China were investigated. According to different functions, nine snowfall sampling points were collected in Harbin, and concentration of PAHs was measured by GC—MS. The results demonstrated that the concentration of 16 kinds of PAHs was ranged from 33.2ng/dL to 2306.6ng/dL in Harbin snowfall, the average concentration was 1144.38ng/dL. The concentration of PAHs had obvious regional difference in different functional areas, its spatial distribution showed that the concentration in rural was 1724.1ng/dL, in commercialtraffic area was 1662.6ng/dL, in city park was 832.0ng/dL, in residence community was 528.6ng/dL and that in suburb was 33.2ng/dL, the concentration in rural and commercialtraffic area was about 50 times lager than that in suburb. Pollution sources and atmospheric diffusion conditions were the major reasons for regional difference of PAHs concentration in snowfall. It was found that the 3~4 rings PAHs content was relatively higher, which accounted for 66.8%~77.3% of total PAHs concentration. The monomer content of PAHs was also quite different, and phenanthrene (Phe) was the highest in all the monomer. In snowfall samples, the 2 ring PAHs was in strong variation, while the other ring PAHs was in moderate variation, pollution sources and physical and chemical properties might be expected to result in existence of PAHs spatial heterogeneity characteristic. Diagnostic ratio and factor analysis method were adopted to analyze the data, preliminary results showed that the source of PAHs in Harbin snowfall were coal and biofuel combustion and automobile emissions. The research results would provide reference and scientific basis for numerical simulation of secondary emission of PAHs during snow melting process, snowmelt runoff numerical simulation and formulation of environmental pollution control measures and its management policies.