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Total suspended particulate (TSP, particle diametera parts per thousand currency sign100 mu m) was the dominant air pollutant and significantly influenced local air quality. In this paper, we investigated the interannual and seasonal variations of TSP and dustfall of the atmosphere over Urumqi, the capital city of Xinjiang Uygur autonomous region, northwestern China, basing on environmental monitoring records and meteorological data from 1986-2012. The results showed that during the study period, annual average TSP concentration decreased from 716 to 260 mu g/m(3), with an average level of 422.9 mu g/m(3), while dustfall intensity reduced from 350.4 to 166.6 t/(km(2)center dot a), with an average level of 259 t/(km(2)center dot a). Over 50% of the annual pollution days were induced mainly by TSP. Spring and winter had relatively higher dustfall intensities, and dense traffic and residential areas had the highest dustfall intensities in the Urumqi metropolitan area. With an annual average precipitation of less than 300 mm, atmospheric particulates in Urumqi could be hardly removed through wet deposition. During spring and summertime prevailing winds from northwest and northeast could carry aeolian dust particles from sandy deserts to Urumqi. Aeolian dusts from deserts would remain to be a priority regarding air pollution control in arid oasis cities.