In order to absorb CO2 on a large scale, several nanocatalysts have been developed as fuel conversion technologies in response to an increase in the concentration of CO2 in the atmosphere. MXene is a young family of two-dimensional metal carbides and nitrides. MXene-based catalysts are nominated for divers who require applications. The selectivity of MXene with high CO2 adsorption capacity, charge carrier, high separation rate, and efficient CO2 conversion efficiency has led to the wide application of MXene and MXene photocatalyst in recent CO2 reduction studies. The specialty of MXene, such as high electrical conductivity, large active area, and large area size, makes MXene a candidate co-catalyst. Although commonly used as a co-catalyst in photocatalytic CO2 reduction, the basic mechanism of MXene is still unknown. Theoretical and computational modeling (firstprinciple density functional theory) is quite effective to understand how MXene and MXene-based photocatalysts affect CO2 reduction. This is supported by the results of further research. In addition to the simulation and calculation, steps of completely understanding the relationship between the layer structure and the phase and determining the type of MXene, the surface functional group, and the characteristics there between may facilitate the achievement of the goals.