In order to study the hydrogeological conditions and main engineering hydrogeological problems of the major project from western Bomi to Nyingchi section in eastern Tibet, On the basis of the previous research results, the relevant research work of key borehole core geological cataloging and field hydrogeological investigation.The results show that there are four types of hydrogeological problems along the route, such as high cold, high steepness, high seismic intensity, high ground stress, high ground temperature and high water pressure. There are mainly four types of hydrogeological problems, such as high water pressure water inrush in deep-buried long tunnel, high pressure water inrush in fracture zone bedrock, thermal damage caused by high temperature hot water, and the influence of tunnel drainage on ecological environment. The predicted water pressure outside the Yigong tunnel is between 0.80 and 3.47 MPa, the predicted maximum water inflow of the Yigong Tunnel and Sejilashan tunnel is close to or over 100 000 m³/d, and the measured bottom temperature of 25 boreholes along the Lanyue tunnel is between 12.5 ℃ and 93.5 ℃.