As a result of supercritical CO₂ dissolution，the physical properties of heavy oil can be significantly improved，and thus leading to a mobilization efficiency. Herein，in order to gain the underlying interactions between heavy oil and supercritical CO₂ deeply，the effect of supercritical CO₂ on physical properties and asphaltene precipitation of two heavy oils was thoroughly examined，and the texture change of the asphaltene from conventional heavy oil and extra-heavy oil before and after CO₂ injection was observed. The results showed that the viscosities of the heavy oils were noticeably reduced due to the dissolution of supercritical CO₂. The dissolved gas-oil ratio of the conventional heavy oil increased with the increasing pressure，while for the extra-heavy oil，the gas-oil ratio was 30 m³/m³ at the saturation pressure. In addition，supercritical CO₂ in the heavy oils caused the asphaltenes to agglomerate and subsequently to precipitate，especially for the conventional heavy oil，which produced approximately 30% more precipitatant than the extra-heavy oil did. Furthermore，the texture of the asphaltenes in the conventional heavy oil was notably altered to be smooth，as revealed by SEM observations. In contrast，a weak alteration of the asphaltene textures for the extra-heavy oil was observed due to the compacted architecture of asphaltenes and resin，which obstructed the entrance of CO₂ molecules.