<p>The progressive failure process and stress–seepage pressure evolution of rock masses around tunnels are significant for preventing and controlling water inrush disasters. This study utilizes a self-developed three-dimensional fluid–solid coupling model test system to examine the impact of karst caves ahead and alongside a tunnel on the stability of the surrounding rock. It also analyzes the variations in stress and seepage pressure of rock masses during tunnel excavation. The model testing results indicate that excavation disturbance significantly impacts the stress–seepage pressure evolution of rock masses. The tunnel excavation's disturbance range is about 1.0-to-1.5 times the tunnel diameter. During tunnel-approaching karst caves, a negative correlation exists between stress and seepage pressure, with seepage pressure gradually decreasing while stress gradually increases. Furthermore, rock masses associated with karst caves at different locations exhibit different stress–seepage pressure evolution. During tunnel excavation approaching the karst cave alongside the tunnel, the seepage pressure gradient exhibits a funnel shape with the center at the midpoint of the karst cave, while the stress gradient shows an inverted funnel shape. After the tunnel moves away by a certain distance, both the seepage pressure and stress remain stable. During tunnel excavation approaching a karst cave ahead of the tunnel, a significant abrupt decrease in seepage pressure gradient indicates the imminent occurrence of a sudden water inrush. The changes in the stress field of the rock mass and the pore pressure inside fractures caused by construction disturbances are the main causes leading to the progressive failure of the rock mass, thereby triggering water inrush disasters. The observed characteristics of changes in seepage pressure and stress, as identified in this study, can provide a theoretical basis for the early warning and prevention of water inrush disasters.</p>