Combining with engineering cases and the creep characteristic of silty mudstone obtained by rock creep test, this paper studied the rheological properties of high-stress silty mudstone and deformation of the deep buried tunnel. Rock creep tests illustrated that the mechanical properties of silty mudstone were part of typical Visco-elastoplastic rheological models. Influenced by the rock rheology, the deformation of surrounding rock presented nonuniform growth trend over time after the tunnel construction. The maximum time-history deformation curves of different depth of tunnel could be divided into three phases. Phase I: linear phase, deformation of linear growth phase took about 55% of the total amount of creep deformation. Phase II: decelerating phase, in this period, the surrounding rock deformation rate got lower and lower while the deformation around the tunnel got stabilized. Phase III: smooth convergence phase, two years after the tunnel add finished, the creep deformation had reached over 90% of the whole, but the slow increase of deformation would still exist for a long time. The ratio of the creep deformation of the three phases was about 5: 4: 1.
