Based on the daily rainfall data from 1952 to 2011 of 28 rainfall stations in Dagu river basin ,the paper analyzed the rainfall temporal and spatial distribution characteristics by conventional statistical, coefficient of variation and IDM spatial interpolation method respectively. The results showed that the precipitation mainly distributes in July and August.The precipitation of the two months accounts for more than half of the annual precipitation.The inclination rate of annual precipitation and the maximal 1-day precipitation is -21.0mm per 10 years and 0.34mm per 10 years respectively.The precipitation in the basin shows upward trend.The spatial distribution characteristics of annual precipitation indicated that the maximal 1-day precipitation and the storm rainfall days (≥50mm) have close relationship with the terrain in the basin. The high values of annual precipitation, the maximal 1-day precipitation and the storm rainfall days (≥50mm) mainly distribute in hilly and mountain area and the low values distribute in plain area generally.