<p>Yangtze River Delta River-Crossing Tunnel is taken as a case study to evaluate the tunnel seepage risk during construction. Numerical simulation is used to quantitatively analyzes the various hydrogeological conditions of tunnel construction process, including soil deformation, soil damage, pore water pressure, groundwater velocity, and the stress of the tunnel’s surrounding rock. The results indicate that soil displacement primarily propagates outward from the center of the excavation face. Construction disturbances cause damage to the soil structure around the tunnel, creating preferential flow paths. However, grouting consolidation and lining installation can effectively control soil deformation, which reduces tunnel seepage risks. Therefore, the significantly higher groundwater velocity near the excavation area will decrease after grouting consolidation. During the construction process, the uneven distribution of surrounding rock stress results in greater stress at the top and bottom of the tunnel where are vulnerable to seepage. This study simulates the change of hydrogeological conditions during tunnel construction, and evaluates the tunnel seepage risk under the variation of hydrogeological conditions. It holds significant theoretical and practical value for the prevention of seepage in construction tunnels.</p>