Covalent organic frameworks (COFs) are a class of stable two-dimensional or three-dimensional porous materials, which are composed of ordered organic units connected by strong covalent bonds. It is precisely because of their outstanding physical and chemical properties that they have become popular materials for research on photocatalytic reduction of CO2 in recent years. In this review, we first summarize the synthesis and structures of COFs. Subsequently, we provide an overview of characterization techniques used for COFs. Finally, we systematically review recent research progress on the photocatalytic reduction of CO2 using COFs. The fully understand of the relations between COFs structures and photocatalytic CO2 reduction would greatly enhancing the further development of this emerging area. In this paper, we address this gap, aiming not only to provide the latest research progress of COFs materials in the photocatalytic reduction of CO2, but also to summarize the advanced characterizations for COFs structure and illustrate the structures guided photocatalytic reduction of CO2 performance.