Abstract: Greenhouse gas emissions from fossil fuel combustion have led to global ecologicaldegradation and energy crisis. Therefore, it is urgent to explore new technologies for the conversion, re⁃use and clean energy production of carbon dioxide (CO2). Compared with the conventional technologyof converting CO2 into high-value products, the conversion of CO2 into methane (CH4), a low-carbonenergy source, using microbial electrolysis cell (MEC) has the advantages of mild reaction conditions,recyclable catalysts and green products, and has received a lot of attention from researchers. This paperreviews the current research status of CO2 capture and high-value resource utilization, and discussesthe main influencing factors of MEC-CO2 electromethanation (such as inoculum source, reactor config⁃uration, applied voltage, electrode material properties, etc.), briefly outlines the important role of e⁃lectron shuttles, especially riboflavin, in MEC - CO2 electromethanation and the biofilm formationprocess of electric methanogenic bacteria, points out the current technical bottleneck and futureresearch direction of MEC-CO2 electromethanation, and finally provides theoretical support for the de⁃velopment of MEC-CO2 electromethanation and the realization of " dual carbon" goal.