The fracture mechanics theory was used to analyze the actual energy release rate at the tip of cracks in the material considering creep deformation. The strain energy accumulation law of microcracks in concrete under continuous loading was investigated and it is concluded that the microcrack extension evolution state is the same under long-term continuous loading and uniaxial loading with the same strain energy accumulation. This model is in good agreement with the results of non-linear creep tests on concrete of different strength classes. The coupling mechanism between concrete damage and creep can be reflected.