Three extreme rainfall indexes as the maximum consecutive rainy days (MCP), the maximum number of consecutive rainy days (MCD) and related maximum precipitation intensity (MCI) and the Z index are defined and analyzed based on the daily precipitation data of 42 rain gauging stations in the period of 1960 -2005. The results indicate that: (1) higher/lower MCP, MCD, MCI and Z values are found in the east/west parts of the Pearl River basin. The annual and summer MCP, MCD, MCI and Z values are high in the Pearl River delta, Guilin, Baise and Chongzuo, implying higher flood risk in these regions. No evident changes of MCP, MCD, MCI and Z values can be observed in winter; (2) No significant abrupt behaviors can be identified in these variables; ( 3 ) The spatial distribution of precipitation extremes is in close relations with that of topography. Those areas with higher probability of precipitation extremes are usually surrounded with mountains and may easily trigger mountainous flash floods. In this sense, the results of this study should be of great scientific and practical merits in scientific water resources management and enhancement of human mitigation to natural hazards.%基于珠江流域1960 - 2005年42个雨量站的日降雨资料,定义了3个极端降雨的指标(最大连续降雨量(MCP)、最大连续降雨天数(MCD)以及最大连续降雨强度(MCI))及通过将三者叠加得到的综合指数Z,运用线性回归模型以及Mann-Kendall法分析了珠江流域极端降雨的时空分布特征.研究结果表明:①珠江流域的MCP、MCD、MCI和Z值在总空间分布上呈东大西小的局势,全年和夏季MCP、MCD、MCI等Z值的高值出现在珠江三角洲、桂林市、百色市等地区,表明上述区域是极端降雨的高发区；②珠江流域近46年的极端降雨事件没有出现显著变异,未发现显著突变；③极端降雨事件的空间分布特征与地形有密切联系,流域内极端降水事件的多发区周围往往有山脉或高大地形环绕,由于山区或者丘陵区地势较高,因而易发生山洪等灾害.
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