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Based on the daily data of PM10 at Sanming，the synchronous data of meteorological elements (pressure, wind speed, temperature, humidity, precipitation, evaporation, etc.) and the synoptic chart data at 08:00 850 hPa from 2004 to 2007, the mutation characteristics of PM10 and the relation between mutation processes of PM10 and meteorological conditions are quantitatively analyzed．The results show that there were some evident seasonal characteristics in mutation events of PM10, and the probability of mutation was greater in winter and spring than those in summer and autumn; when surface pressure fell，wind speed decreased，relative humidity decreased, precipitation reduced, temperature and evaporation increased, it was more likely for PM 10 to have positive mutation; when surface pressure went up, wind speed rose, relative humidity and precipitation increased, temperature and evaporation decreasesd， it was more likely for PM 10 to have negative mutation; PM 10 was easier to have positive mutations when influenced by the posterior of a continental high pressure or the warm sector of a convergence system; it was easier to have negative mutations while influenced by the anterior of a continental high pressure or a shear line.