CO2 replacement of CH4 from natural gas hydrate is a very promising method to exploit natural gas hydrate, this method has the dual advantages of energy safe exploitation and greenhouse gas formation storage. Firstly, the research progress of CO2-CH4 hydrate displacement in porous media is reviewed and the key bottleneck problems, such as long reaction cycle, slow rate and low efficiency, which restrict the commercial application of CO2 displacement method to the exploitation of natural gas hydrate, are analyzed. In view of this problem, the research progress of strengthening methods for CO2-CH4 hydrate replacement in porous media is comprehensively reviewed. It includes the enhancement of liquid CO2, the enhancement of small molecules such as N2 and H2, the enhancement of prolongation of reaction time, the enhancement of application of adsorption materials with both CO2 and CH4 gas absorbability and the analysis of new ideas enhanced mass transfer during displacement due to the formation of porous CO2 hydrate. At the same time, the characteristics of various strengthening methods are analyzed. Primarily, different phase states of CO2, small molecules and mixed gases reinforcement replacement and the mechanism of other reinforcement methods are described in detail, and the improvement of various reinforcement methods is discussed. Studies show that, for the overall recovery rate, replacement combined with conventional methods is more effective than introducing small molecule mixture and changing the injected phase state of CO2. Therefore, the combined enhancement of the single method is an effective way to improve the replacement efficiency. Finally, the shortcomings of the current research and the future research direction of the enhancement of CO2-CH4 hydrate displacement process in porous media are proposed.