The stochastic properties and discreteness of macroscopic property for concrete appear on mechanical property and fracture surface. In consideration of stochastik and discreteness of fracture surface, a class of mesoscopic damage mechanics model of concrete based on spring model, are put forward to understand the real damage evolution characteristics of concrete at the level of constitutional law. A kind of spring-slipper model is introduced to reflect the elastic-plastic damage behavior. It has been confirmed that fracture surface of concrete has self-affine fractal characteristic only on a certain spatial scale, but the actual fracture surface of concrete is a stochastic surface with multi-fractal characteristics. Uniaxial test was operated, combined with the Computerized Tomography test of concrete, to study the evolution of crack surface from mesoscopic level to macroscopic level. Compared with the existing damage constitutive law and experimental results preliminarily, the feasibility of fractal damage constitutive law is verified.