[Purposes] CO₂ phase change fracturing technology has the advantages of environmental protection, low risk, and easy control, and it is widely used in mineral mining, engineering construction, and other fields. Exploring the evolution law of CO₂ phase change fracturing-induced damage is of great significance for the selection of blasting construction parameters. [Methods] In response to the limitations of the damage model of equivalent explosives to describe CO₂ phase change rock breaking process, the ideal gas state equation was used to describe the supercritical CO₂ phase change process. Combined with the Mises criterion, a calculation model for rock damage radius under phase change was given. Based on LS-DYNA software, a rock damage calculation model under phase change was established, and the evolution law of rock damage under phase change was analyzed. Furthermore, the influence of parameters such as the fracturing pressure and the type of fracturing tube on the evolution of rock damage was analyzed. [Findings] The established model for calculating the rock damage radius under phase change can effectively evaluate the damage range of rocks. Phase change impact causes radial cracks in the rock, and CO₂ phase change gas is embedded in the cracks near the main crack. The crack tip effect promotes the formation of denser circumferential cracks and smaller axial cracks in the rock mass. According to numerical simulations, the range of crack zones generated by the type 85 fracturing tube is 0.42, 0.43, and 0.46 m, respectively, under fracturing pressures of 174, 250, and 290 MPa. The increase amplitude of crack length slows down with the increase in pipe diameter. The average length of cracks generated by the three types of fracturing tubes including type 51, type 85, and type 100 under a fracturing pressure of 290 MPa is 13.2%, 5.75%, and 1.41% higher than that under 174 MPa, respectively. When the fracturing pressure is 250 MPa, the range of crack zones generated by the three types of fracturing tubes is 0.42, 0.43, and 0.47 m, respectively. Under the three fracturing pressures, the average crack length generated by the type 100 fracturing tube increases by 14.2%, 11.1%, and 2.4% compared to that generated by the type 51 fracturing tube. In addition, with the increase in the fracturing pressure and the diameter of the fracturing tube, the main and circumferential cracks generated by phase change fracturing increase, and the average crack length of the rock increases. [Conclusions] The results can provide a reference for damage control and technical parameter selection in CO₂ phase change fracturing construction.