Abstract: Bending deformation of rock strata occurs due to force and fold structure is formed thereof, further it is liable to have deformation failure of tunnel surrounding rocks under influence of complex geological structure and geostress, affecting tunnel stability. Aiming at the surrounding rock deformation of tunnel which is parallel to fold axis and passing through fold structure geology, finite difference method is adopted to conduct numerical simulation and calculation, to explore the deformation law, and to put forward the thought of deformation control of tunnel surrounding rocks. The results show that deformation is more likely to occur at tunnel crown and invert and mainly concentrated in the soft rock stratum and the soft-hard rock interface when the tunnel passes through the parallel fold structure with being parallel to the fold axis, specifically they are at the upper boundary of synclinal soft rock stratum and the lower boundary of anticlinal soft rock stratum, and it is considered to control deformation at tunnel crown and invert and to reinforce the soft rock stratum of parallel fold structure to reduce the deformation of tunnel surrounding rocks.