To address the problem of CO₂ utilization and storage （CCUS）， injecting CO₂ into reservoirs to enhance crude oil recovery while storing CO₂ is a green， economical and efficient production model. In this study， a three-dimensional three-phase multi-component numerical model for reservoir extraction was developed to study the extraction and storage effects. The results show that CO₂ can effectively reduce the viscosity of crude oil and significantly promote the recovery rate. The cumulative oil production at 400 d with CO₂ injection is 32 times higher than that with water injection. This shows that the extraction means of CO₂ injection has a promising future. The research in this paper further understands CCUS， which is of great significance for achieving China''s strategic goals of carbon peaking and carbon neutrality.