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The analysis of the statistical data of grain production and disaster area from 1985 to 2004 in Fujian Province indicates that the disaster area in Fujian Province is inversely correlated with grain yields; the severity and impact of meteorological disasters on grain yields increase year by year. The sensitivity of grain yields to meteorological disasters is studied with the ratio of the grain yield variation rate after eliminating the plating area variation to the variation rate of the disaster area. The resulting sensitivity explains well the fact that disasters increase, but grain yields increase also from the 1980s to the 1990s; and that grain yields decrease obviously, but disasters increase slightly in the early 21 century.