Abstract: As for the rock mass deformation and geological hazards of deep-buried hard rock tunnels, based on the calculation method of the fractural theory, it studied the fractal features of rock mass deformations during the construction of deep-buried water conveyance tunnels of Jinping II hydropower station. The results show that it has the temporal fractal characteristics for the deformation of surrounding rocks during the construction of deep rock tunnels, and it exhibits good self-similarity structural features; under the same buried depth, the maximum fractal dimensions occur at the tunnel crown, then it decreases at spandrel, and the minimum fractal dimensions occur at the side wall; as for the tunnel with buried depth of 500-1 800 m, the larger the buried depth is, the larger the increase of deformation fractal dimensions and the occurrence frequency of surrounding rock hazards; as for the tunnel with buried depth more than 1 800 m, the deformation fractal dimensions and the occurrence frequency of surrounding rock hazard tend to be stable and the buried depth has a little effect on it.