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The snow disaster variation and its circulation characteristics in the early winter are analyzed by use of the meteorological data of air temperature, precipitation and snow cover in the early winter over the southern Qinghai Province from 1961 to 2004. The result shows that snowfall over the southern Qinghai Province had been decreasing; the averaged snow cover had a slight decreasing trend comparing with other seasons, which was negatively correlated with air temperature, but positively correlated with snowfall. The principal synoptic systems of impacting snowfall in the early winter were the combinations of the westerly and southtonorth trough, moving plateau trough, plateau low pressure, plateau shear line, Bangladesh Bay storm; the configuration of the 850 hPa temperature anomaly field of the southern and middle Asia in the typical snowabundant/scarce year on the plateau was “positive in the south and negative in the north”, while the anomaly distribution of 500 hPa on the plateau and the eastern coastal area was “low in the west and high in the east”.