Abstract: Understanding how internal damage mechanisms affects the deformation behavior at each rock deformation stage (compaction, linear elasticity, elastoplasticity, residual) is key to analyzing multi-stage failure. However, existing models often neglect the damage accumulation caused by crack initiation in the linear elastic stage and the accurate definition of the yield criteria also remains challenging. To address these limitations, this study proposes an improved endochronic damage model incorporating micro-damage to better capture rock deformation and damage evolution through the whole failure process. First, an endochronic compaction coefficient is introduced to capture nonlinear pore closure effects, improving the model's compaction stage representation. Second, a Weibull-based damage equation using endochronic measures is established to quantify damage accumulation starting from the linear elastic stage, with systematic parameter interpretation. Results show that the model aligns well with experiments, outperforming traditional models in simulating compaction stage deformation and capturing fracture-induced damage evolution, thereby validating its accuracy and applicability.