Abstract: The Jilintai Hydropower Station in located in a region with strong modern tectonic activity.The recent faulting has an important influence on the safety of the station.During the field investigation,a series of fault rock samples were collected along the faults in the station area,and analyses of deformation microstructures and quartz surface textures,as well as isotopic dating techniques have been used in lab for comprehensive research.The results show that the lower and upper limits of time of the last strong faulting are 130-200 and 90-150ka,respectively.The results of structural model experiments indicate that under the action of modern tectonic stress field,the engineering site area will uplift as a whole,but new fault system and stress concentration zone will not occur in future.Therefore,the sellected station site is a relatively stable place in this tectonically active region.