Based on monthly observed precipitation data at 19 meteorological stations in the Ningxia and 74 atmospheric circulation exponentials data of the National Climate Center, the temporal and spatial distribution characteristic and predictability were analyzed by variance, Empirical Orthogonal Function (EOF) , Optimal Subset Regression (OSR). Results indicated that the coefficient of variance of precipitation in winter was bigger. The variance contribution of EOF1 changed with 'U' trend, while that of EOF2 changed conversely; the spatial distribution was divided into three areas form north to south. The history return fitting accuracy rate was different from Jan to Nov, it maintained at a high level during January to April, but then gradually decreased to the minimum in May.%针对宁夏全境19个气象观测站的月降水资料和全球74类大气环指数资料,利用方差分析、EOF分解、最优子集回归回报检验等方法分析了时空分布特征和可预测性.结果表明,冬季各月降水偏离平均值的程度较大；各月降水EOF1的方差贡献率1～12月的整体趋势为下凹型分布,EOF2呈相反趋势变化；月降水的EOF1空间分布从南到北大致分为3个带状区域；利用OSR方法回报检验各站的历史拟舍率很不均衡,1～4月维持一个较高的拟合率,然后逐渐降低,5月达到一个最低值.
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