To address challenges such as uneven permeability，poor crude oil mobility，and high extraction difficulty in tight reservoirs，three kinds of modified nano-SiO₂ particles with amphiphilicity，hydrophobicity and hydrophilicity were prepared by silane coupling agent homogeneous modification method and Pickering emulsion method to modify ordinary nanoparticles with particle size of 20—40 nm，which could adapt to small pores in tight oil reservoirs. Through the analysis of stability，interfacial activity and wettability，the amphiphilic Janus nano-SiO₂ particles were selected，and the subsequent imbibition displacement experiment was carried out. The results showed that the absolute value of Zeta potential of amphiphilic Janus SiO₂ nanoparticles could reach up to 31.01 mV. The transmittance of the dispersion reached 93.3% after standing for 3 days，and the transmittance of the dispersion had the smallest change. Amphiphilic Janus SiO₂ nanoparticles could reduce the oil-water interfacial tension to 0.37 mN / m. The amphiphilic Janus nano-SiO₂ particles could change the wettability of the core，reduce the capillary force in the reservoir pores，increase the fluidity of the oil phase，and achieve the effect of reducing pressure and increasing injection，so as to improve the oil displacement efficiency. The results of core simulation imbibition oil displacement experiment showed that the imbibition recovery rate（19.48%）of amphiphilic Janus nano-SiO₂ particle dispersion with a mass fraction of 0.01% was 12.23 percentage points higher than that of simulated formation water（7.25%），and 8.6 percentage points higher than that of ordinary nano-SiO₂ particle dispersion. With the increase of hydrophilic Janus nano-SiO₂ particle concentration，the imbibition recovery rate increased，and the recovery rate could reach up to 25.71% at a mass fraction of 0.05%. It is feasible to apply Janus amphiphilic nano-SiO₂ particles to enhance oil recovery in tight reservoirs.