Abstract: Photocatalytic reduction of CO₂ can not only reduce the CO₂ content in the atmosphere but also convert CO₂ into useful chemicals such as CO, CH₄, HCHO and HCOOH,thus solve the problem of energy shortage and environment pressure.g-C₃N₄ has become an important material for research due to its excellent photocatalytic properties, due to its two-dimensional layered structure, a narrow band gap and easy structure adjustment. This paper reviews the construction of g-C₃N₄-based photocatalytic materials and their research progress in CO₂ catalytic conversion property. The structure and preparation of g-C₃N₄, the reaction mechanisms of CO₂ reduction, and the modification of g-C₃N₄-based photocatalytic materials were discussed in detail. The paper elaborates on the process of photocatalytic CO₂ reduction and explores the impact of surface modification, molecular structure modification, morphology modification, and heterostructure construction of g-C₃N₄ on the efficiency of CO₂ reduction. Finally, some challenges faced by this field was analyzed and prospected.