A severe rainstorm occurred in southwest part of Leizhou Peninsula for the period of August 8 to 11, 2007, with both daily and hourly rainfalls exceeding the maximum of historical observations. This paper analyzes the characteristics of total, daily and hourly rainfall, discussing the relationships of the heavy rain with paths of tropical cyclones "Pabuk" and "Wutip", weather pattern, variations of satellite cloud images and radar echo, respectively. The results show that this heavy rain is characteristic of high intensity, long duration, large amount and concentrative location. In the early stage, heavy rain occurred in Leizhou Peninsula on account of the effects of the "Pabuk" circulation and its outer region cloud system. In the subsequent stage after the early morning August 10 the track of "Pabuk" turned, the circulation adjusted, and the center of rainstorm sustained and swayed over southwest part of Leizhou Peninsula for a long period of time as a consequence of the interactions of the "Pabuk" circulation, the outer region cloud system and the cold vortex cloud clusters over the Beibu Gulf. Such a weather situation was in favor of the convergence of a huge amount of energy and water vapor, and the southern and northern convective cloud systems and radar echoes meeted in southwest part of Leizhou Peninsula, leading to a severe flood disaster.