Abstract: In order to investigate the influential factors of gas desorption hysteresis effect and optimize the extraction process in 3# coal seam of Yecheng Mine, the evolution law of the pore structure of coal samples after heat treatment was analyzed experimentally, which revealed the significant influence of the temperature on the volume and connectivity of the fissures.Meanwhile, the adsorption and desorption characteristics of coal samples on CH₄ and CO₂ under different temperatures and pressure conditions were studied.It was found that the adsorption capacity of CO₂ was significantly stronger than that of CH₄, and the increase of temperature could effectively reduce the desorption hysteresis effect.Based on the experimental results, a three-in-one heat injection and extraction efficiency enhancement technology of “temperature field reconstruction-pore expansion-competitive adsorption” was proposed, and process parameters such as heat injection temperature, gas injection pressure and gas selection were optimized.The study shows that the combined heat injection-CO₂ extraction technology can significantly improve the gas extraction efficiency, which provides theoretical basis and technical support for the development of deep coalbed methane.