The stability of a foam flooding system is one of the main factors affecting the enhanced oil recovery (EOR) efficiency of foam flooding technology. Using silica nanoparticles (SiO?) as foam stabilizers can reduce the impact of high salinity, high calcium ion concentration, and other factors on foam performance, thereby improving foam stability. However, conventional silica nanoparticles suffer from poor dispersibility, a tendency to aggregate, lack of functionality, and high cost, which severely limits the application of foam flooding technology. In this paper, the effects of different hydrophilic/hydrophobically modified nano-SiO?on the stability of foam flooding systems are systematically investigated.Six types of nanoparticles (MA, MB, NA, NB, HA, HB) with different hydrophilic and hydrophobic properties were prepared by homogenizing and heterogeneous modifying nano-SiO2 with different silane coupling agents. Their structures, dispersibility and wettability were characterized by FTIR, particle size analysis, Zeta potential, light transmittance and wetting Angle. The amphiphilic modified nano-SiO2 has the best dispersion stability, followed by the hydrophilic modified one, and the hydrophobic modified one is the worst. Both hydrophilic and amphiphilic modified nano-SiO2 can enhance the water wettability of the core surface, and the minimum core contact Angle can be reduced to 39.6°. In the evaluation of foam performance, the carboxylic acid hydrophilic modified NA has the best foam stabilization effect, with a foam half-life of 108 min and a foam comprehensive index of 16,087.50 mL·min. NA enhances the liquid film strength, slows down the drainage and roughening rate, and significantly improves the foam stability through the hydrophilic and hydrophobic properties of surface functional groups and their arrangement behavior and synergistic effect at the gas-liquid interface. The nanoparticle NA stabilized foam system has good deformability, blocking property and emulsifying oil-carrying capacity in the pore structure.