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Based on the observation data of nine kinds of lowvisibility phenomena (mist, fog, snowstorm, blowing snow, smoke, haze, sand storm, blowing sand, and dust) in Sichuan Province from 1981 to 2013, we discuss the number of occurrence days, occurrence probability, and space distribution characteristics. The results show that the number of occurrence days of lowvisibility phenomena in Sichuan Province was: mist > fog > haze > dust > smoke > blowing sand > sandstorm > blowing snow > snowstorm. The numbers of mist and fog days were 176 days and 29 days, and the probability of daily occurrence was 48% and 8%, far higher than other weather phenomena. As for seasonal variation, fog and haze mainly occurred in autumn and winter, and haze, blowing snow, and snowstorm in winter, sand dust in spring, dust storms mainly in winter and spring, and smoke mainly in spring and autumn. The trend of mist in Sichuan remained stable; the smoke was increasing; and the fog, haze, sandstorm, blowing sand and dust were descending. The stable atmosphere, sufficient water vapor, week wind, concentrated population and large emissions were favorable to the formation of fog, mist, basin haze and smoke. Unreasonable use of water and land resources and dust weather in North China along with the southward movement of cold air are the important causes of sand dust weather. Blowing snow and snowstorm occurred in the western Sichuan plateau with larger winter snowfall and higher wind speed.