Abstract: The current study on damage constitutive model of jointed rock mass considers only the macroscopic damage caused by defects such as joints without considering the microscopic damage caused by defects such as micro-crack in rock blocks. Aiming at the above-mentioned shortage, the jointed rock mass constitutive model combining macroscopic and microscopic damage is proposed. The microscopic damage model is a statistical damage based on strain strength theory and the strength characteristics of rock micro-unit with Weibull distribution, which is used in rock blocks cut by joints. While the macroscopic damage model is mainly based on continuous media mechanics principle, deterioration of rock mass property caused by joints is regarded as damage. On the basis of considering compression and shear transfer coefficient of the joint, the constitutive model of jointed rock mass by combining macroscopic and microscopic composite damage is proposed. The calculation example indicates that existence of the joint greatly weakens the strength of rock mass, reduces its stiffness and enlarges its flexibility. So, the proposed constitutive model can reflect the effect of macroscopic and microscopic damage on rock mass stress-strain relationship and strength, which is rational.