In view of the limited effect of conventional liquid-based chemical agents on inhibiting asphaltene precipitation and the difficulties in implementing the method on site，a method of preparing a solvent-free inhibitor by dissolving nanoparticles into supercritical CO₂ at high pressure was proposed. Based on the understanding of the fluid state and cloud point pressure of the nanoparticle-CO₂ mixture，the study conducted phase pressure measurement，static asphaltene precipitation measurement，and gas-drive core experiment to investigate the effects of graphene oxide（GO），silicon dioxide（SiO₂）and ferric oxide（Fe₃O₄） nanoparticles on the mixing pressure，asphaltene precipitation，and asphaltene particle size after CO₂ injection into crude oil， verifying the feasibility of nanoparticle-CO₂ mixture inhibiting asphaltene precipitation and enhancing oil recovery. The experimental results showed that the nanoparticle-CO₂ mixture was a single-phase fluid at the target reservoir temperature and pressure，and its cloud point pressure increased with the increase of nanoparticle concentration and temperature. Compared with injecting pure CO₂，the addition of GO，SiO₂ and Fe₃O₄ with mass fraction 1% into the CO₂ could reduce the mixing pressure by 16.4%，12.2% and 14.7%，respectively，reduce asphaltene precipitation by 55.4%，32.1% and 37.5%，respectively，and reduce the average particle size of precipitated asphaltene from 11.3 μm to 1.3，8.3 and 5.8 μm，respectively. During the gas drive process， the proportion of asphaltene precipitation decreased from 0.81 to 0.16，0.53 and 0.36，while the reduction in permeability of the core decreased from 88.7% to 25.2%，60.4% and 47.1%. The oil recovery rate increased from 36.7% to 47.4%，39.6% and 42.7%. In particular，GO could significantly adsorb asphaltene molecules，strengthen the stability of asphaltene molecules in colloids， inhibit their aggregation growth，delay precipitation and deposition，and avoid pore throat blockage. The research results provide reference and guidance for improving the gas injection development effect of asphaltene oil reservoirs.