陕西省是我国山洪灾害比较严重的省份之一。在对陕西省山洪灾害调查分析的基础上，重点研究了陕西省山洪灾害的形成成因和分布规律。结果表明，陕西省山洪灾害的形成与陕西省的降雨分布、地质地形以及人类活动有关，陕南的降雨分布和地质地形决定了陕南秦巴山区是陕西省山洪最严重的区域。

Shanxi Province is one of serious provinces in torrent disasters. On the basis of a lot of investigations, the authors research the reason of torrent disasters and distribution law in Shanxi Province. The results show rainfall, terrain and the human activities are the cause of mountain torrent disasters. According to the rainfall and terrain analysis, the number of mountain torrent disasters in Qinba mountain region is the largest than that of other regions in Shanxi Province.