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The relationship between surface wind direction and air pollutant concentration in Shanghai is studied. The same trend in the distribution of the monthly mean concentrations is found as in the frequency of west winds (SSW NNW). The wind rose charts of mean PM 10 concentrations in different seasons are obtained. It indicates that high concentrations usually associate with west winds. Divided into winter half year and summer half year, the averages and standard deviations of the daily variations of pollutant concentrations along with the daily shifts of wind directions are recorded. The daily variations of concentrations increase to some extent when the wind directions shifting from non west to west or under continuous west wind. PM 10 concentration is more sensitive to the shifts of wind direction than those of SO 2 and NO 2.