Currently, the concentration of carbon dioxide (CO2) in the atmosphere continues to rise, and it is a major cause of environmental problems such as global warming. Therefore, the policy which CO2 is considered as a resource, and the generated CO2 is separated / captured and recycled as fuel or material to reduce CO2 emissions (CCUS: Carbon dioxide Capture, Utilization and Storage) was shown. The technology for conversion of CO2 to highly versatile substances such as carbon monoxide (CO) and ethylene (C2H4), which will lead to CO2 fixation and can replace existing fossil fuel-derived materials, holds great promise for the realization of CCUS. We are developing CO2 reduction catalysts based on porphyrin complexes and metallic copper with the aim of realizing CCUS.