ABSTRACT The catalytic CO 2 hydrogenation to produce valuable fuels and chemicals holds immense importance in addressing energy scarcity and environmental degradation. Given that the real catalytic reaction system is complex and dynamic, the structure of catalysts might experience dynamic evolution under real reaction conditions. It implies that the real active sites might only generated during the reaction process. The induction factor of dynamic evolution of active sites could be reactants, intermediates, products, and other local chemical environments. Utilizing in‐situ/operando characterization techniques allows for the real‐time observation of the dynamic evolution process, further combining multiscale theoretical simulations can effectively reveal the refined structure of real active sites and catalytic mechanisms. Herein, we summarized the latest advancements in understanding the dynamic active sites and catalytic mechanisms during the real reaction process for the CO 2 hydrogenation to C 1 products (CH 3 OH, CO, and CH 4 ). The dynamic evolutions of the catalyst in morphology, size, valence state, and interface between active component and support were discussed, respectively. Future research could benefit from more in‐situ characterization and theoretical simulation to explore the microstructure and reaction mechanism, aiming to produce high conversion and selectivity catalysts for CO 2 hydrogenation reactions.