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The climatic conditions and weather patterns of seven typical sandstorms from 2000 to 2003 over Heilongjiang Province, as well as the resulting air pollution, especially particle pollutants, were analyzed. It was concluded that the climatic conditions for sandstorm occurrence include high temperature, strong winds in spring and persistent rainless periods; there are four kinds of weather patterns favorable to the occurrence of air pollution during sandstorm weather. Furthermore, the conditions of air pollution, especially the particle pollution in Harbin were analyzed. Under the effect of sandstorm weather, the particulate concentration increases rapidly, and as a result, the medium to serious air pollution events occur in Harbin.