Abstract: By revising the resistance coefficient, a new self-bearing capacity coefficient of rock mass is proposed in this study to evaluate the bearing capacity of rock mass, and its physical meaning is also given. A circular opening in the ideal elastic-plastic rock mass is taken as an example to derive the self-bearing capacity coefficients K_c under contraction and K_e under expansion, and parametric studies are discussed. The obtained results show that the self-bearing capacity coefficient of rock mass is a comprehensive evaluation index by multiple factors, which is significantly influenced by stress state and wall pressure, and increases with strength parameters of rock mass and the unified strength theory parameter. With the increase of the dilation parameter, the coefficient K_c decreases, whereas the coefficient K_e increases. The effects of changes in strength parameters of rock mass, intermediate principal stress and dilatancy should be fully considered in order to take full advantage of the latent potentialities of rock mass.