［Purposes ］ The concrete lining of compressed air energy storage （CAES） power plants is susceptible to cracking under thermal cyclic loading，and the study of the cracking characteristics and influencing factors of the lining during operation is the key to ensuring the sealing and stability of the power plant.［Methods］ In this paper，the extended finite element method （XFEM） was used to establish a thermo -mechanical coupling numerical model based on Abaqus platform，and the maximum principal stress criterion and fracture energy criterion were adopted as the criteria of concrete cracking and evolution to systematically study the effects of temperature，pressure，and concrete strength on the cracking characteristics of the lining.［Findings］ The cracks initially emerge at the connection corners of the lining and the plug and then expand along the sidewalls to form penetration cracks；an increase in the upper limit of temperature and pressure significantly increases the width，area，and volume of the cracks and shortens the time required for cracking stabilization，while the cracking pattern is reversed when the concrete strength is increased.When the upper temperature limit is increased from 30 ℃ to 50 ℃，the crack width increases by 34.9%；when the upper pressure limit is increased from 6 MPa to 10 MPa，the crack width increases by 70.7%；whereas，the increase in concrete strength from C25 to C 40 can effectively inhibit crack development，and the width of the cracks of the C 40 concrete lining decreases by 47.6% compared with that of the C 25 concrete.In addition，the crack width and volume after cracking stabilization show the phenomenon of tension and closure cycle due to cyclic loading of temperature and pressure，while the crack area remains constant.［Conclusions ］ The results of the study provide a theoretical basis for optimizing the selection of lining materials for gas storage reservoirs and the control strategy of operating temperature and pressure，which is of great significance for improving the safety and durability of the CAES system.