Due to the strong surface disturbance caused by the "5.12" Wenchuan earthquake,mountain torrent disasters have occurred frequently in Wenchuan County in recent years,causing serious damage to local houses. In Wenchuan County,two mountain torrent disasters,"8.20" and "8.17",occurred in 2019 and 2020. Taking some of the damaged village buildings in the two disasters as research objects,this paper summarized the damage characteristics of different structural types of buildings,the spatial variability of the damage degree of buildings along the river and the building masking effect,as well as the damage modes of impact,scouring,siltation and immersion through disaster data mining and typical case analysis. Based on the research and analysis,this paper improved the existing building damage grading criteria by combining the characteristics of mountain torrent damage,and then proposed the classification of mountain torrent damage to rural buildings. Applying random forest algorithm and statistical analysis methods,the main influencing factors of building flood damage and their relationships were comprehensively analyzed in terms of water depth exposure,site exposure,and physical vulnerability. Finally,based on the analysis of building damage,some suggestions were proposed to improve the flood mitigation capacity of buildings in mountainous villages. The research results lay the foundation for further research on the physical mechanism of building flood damage,and also provide references for flood prevention planning and disaster mitigation design of buildings in mountainous villages and towns.