Abstract: Based on the mechanical characteristics of rock and its mechanical properties before and after the peak stress and in combination with its damage characteristics，a three－dimensional continuous damage evolution equation was derived．By using Mohr－Coulomb strength criterion and continuous damage mechanics method and considering the spatial effect in roadway excavation process，the distribution sum of the damage stress of the rock in a non－uniform stress field and the analytical solution of the interaction force when the surrounding rock and support reached equilibrium were analyzed and devived．The support design and monitoring at the site verified the validity of the calculation and analysis，so it has a certain application prospect in the practical engineering calculation．