Beijing, Tianjin and Hebei were divided into five different climatic sub-regions according to their natural geographical conditions and climatic geographical distribution characteristics. 87 meteorological stations with complete data series and relatively long time series were selected, and linear regression, Mann-Kendall mutation test, sliding t test and Morlet wavelet function were used. Statistical method was used to analyze the temporal and spatial variation characteristics of precipitation in five sub-regions and the whole region, using daily precipitation data from 1960 to 2015. The results showed that in the past 56 years, the annual average precipitation of Beijing-Tianjin-Hebei region and its five sub-climatic zones had shown a whole consistency, both showing a downward trend of fluctuations, and the downward trend in the eastern Hebei plain region was significant, but there was no obvious mutation; there was a more significant seasonal, the downward trend of summer precipitation in the region was obvious. Besides the Taihang Mountains, the summer precipitation in other climatic regions showed a decreasing trend, and the eastern Hebei Plain had the largest reduction range, and the Yanshan Hills had a significant abrupt change in 1996. All the climatic regions and sub-climatic regions had the fastest reduction rate. The annual and seasonal precipitation showed significant interannual and interdecadal or interdecadal variations. There were four main periodic variations, which were roughly divided into 3-4 years, 6-10 years, 12-18 years and more than 20 years.%按照自然地理条件和气候的地理分布特征把京津冀分为5个不同的气候子区域, 选取资料序列完整且具有较长时间序列较为均匀分布的87个地面气象站, 运用线性回归、Mann-Kendall突变检验、滑动t检验、Morlet小波函数等统计方法, 选用1960—2015年逐日降水观测数据, 分别对5个子区域及全区的降水量进行时空变化特征分析.结果表明, 近56年来京津冀全区及5个分气候区年平均降水量变化呈现整体的一致性, 均呈波动下降趋势, 冀东平原区下降趋势显著, 但均未发生明显突变现象;存在较为显著的季节性, 全区夏季降水量下降趋势显著, 并于1996年发生突变, 总降水量中以7月和8月贡献最大, 降水量减少速率也最快;除太行山区外, 其他分气候区夏季降水量均呈减少趋势, 且冀东平原区减少幅度最大, 燕山丘陵在1996年发生了明显突变;全区及各分气候区年、季降水量呈现显著的年际和年代或多年代际变化, 主要存在4个周期变化, 大致分为3～4、6～10、12～18和20年以上.
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