Analyzing correlation between annual precipitation and the M ≥6 earthquakes in Yunnan since 1960, we find that when the mean annual precipitation in Yunnan is less than 1 000 mm, or the number of the stations whose annual precipitation anomaly is lower than 25% is larger than 20, the corresponding probabitity of M≥7 earthquake in Yunnan in the following year is only 25% and 33% respectively. The correlation between the drought anomaly and the M≥7 earthquake isn't significant Analyzing the spatial distribution of precipitation in Yunnan, we find that one year before the M≥6 earthquakes more than 80% of the total, the annual precipitation near the epicenters of the earthquakes is 20% higher than the average. The correlation between the flood a-nomaly and the M≥6 earthquakes happened in Yunnan is significant We think that the precipitation loaded on the crust may trigger the earthquake, but it is only a modulator. The intrinsic factor is decisive for the earthquake.%通过对1960年以来云南地区的年降水与M≥6地震的相关性进行分析,发现云南全省年降水平均值小于1000mm或年降水距平值低于多年平均降水量25％的台站数大于20,出现降水旱异常后,与次年云南地区发生7级地震的对应率分别为25％和33％,没有显著的相关性；从降水的空间分布特征分析,云南除思茅、普洱地震区外,有80％的M≥6强震在震前1年,震中附近出现过降水大于多年均值20％的现象,云南降水涝异常与6级以上地震存在一定的相关性,但分析认为降水通过对地壳的加载可能对地震有一定的诱发作用,但最多只是外因,只起调制作用,地震的发生主要是内因起主导作用.
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