This study presents the preparation of amphiphilic Janus-SiO₂ nanoparticles and evaluates their oil displacement effect in high-salt, low-permeability reservoirs. The nanoparticles were synthesized by modifying SiO₂ nanoparticles with trichloro(octyl)silane and aminopropyl triethoxysilane through interface protection modification. The resulting amphiphilic Janus-SiO₂ nanoparticles have a hydrophobic carbon chain and a hydrophilic amino group, enabling good dispersion in mineralized water and maintaining interfacial activity despite changes in salinity. The interfacial tension between the nanoparticle dispersion and crude oil remains in the order of 10⁻² mN/m, indicating excellent interfacial activity. The nanoparticles adsorb on the rock surface, enhancing its hydrophilicity and improving oil recovery. Under conditions of 65°C and 8000 mg/L salinity, injecting 0.5 PV of 0.05% amphiphilic nanoparticle dispersion increased oil recovery by 14.6% compared to water flooding. The mechanism of oil displacement involves reducing oil-water interfacial tension, changing rock wettability, and enhancing the shear viscosity of the oil-water interface. The amphiphilic Janus-SiO₂ nanoparticles show good performance in high-salt and low-permeability reservoirs, with potential for application in such environments. The study also highlights the importance of maintaining nanoparticle dispersion stability to ensure effective oil displacement in tight reservoirs. The results demonstrate that amphiphilic Janus-SiO₂ nanoparticles can significantly improve oil recovery in challenging reservoir conditions.This study presents the preparation of amphiphilic Janus-SiO₂ nanoparticles and evaluates their oil displacement effect in high-salt, low-permeability reservoirs. The nanoparticles were synthesized by modifying SiO₂ nanoparticles with trichloro(octyl)silane and aminopropyl triethoxysilane through interface protection modification. The resulting amphiphilic Janus-SiO₂ nanoparticles have a hydrophobic carbon chain and a hydrophilic amino group, enabling good dispersion in mineralized water and maintaining interfacial activity despite changes in salinity. The interfacial tension between the nanoparticle dispersion and crude oil remains in the order of 10⁻² mN/m, indicating excellent interfacial activity. The nanoparticles adsorb on the rock surface, enhancing its hydrophilicity and improving oil recovery. Under conditions of 65°C and 8000 mg/L salinity, injecting 0.5 PV of 0.05% amphiphilic nanoparticle dispersion increased oil recovery by 14.6% compared to water flooding. The mechanism of oil displacement involves reducing oil-water interfacial tension, changing rock wettability, and enhancing the shear viscosity of the oil-water interface. The amphiphilic Janus-SiO₂ nanoparticles show good performance in high-salt and low-permeability reservoirs, with potential for application in such environments. The study also highlights the importance of maintaining nanoparticle dispersion stability to ensure effective oil displacement in tight reservoirs. The results demonstrate that amphiphilic Janus-SiO₂ nanoparticles can significantly improve oil recovery in challenging reservoir conditions.