In the case of the severe inadequacy in replacing chemical flooding reservoirs currently，there is an urgent need to tackle and break through the technology for enhancing oil recovery in high-temperature and low-permeability oil reservoirs. The smart nano black card oil displacement technology is a highly forward-looking nanotechnology for enhanced oil recovery，which has the potential to significantly enhance oil recovery. According to the condition of high temperature and low permeability reservoir in Henan oilfield，the static performance evaluation of smart nano black card（SNBC）under high temperature condition was carried out，and the oil displacement effect of SNBC under different permeability conditions was evaluated by high temperature core displacement experiment. The results showed that the SNBC had excellent high temperature resistance and good dispersion stability. SNBC could reduce the oil-water interfacial tension to 10^-1 mN/m，and had the ability to change the wettability and emulsify and demulsify rapidly. At the same time，the SNBC had a high efficient oil washing ability. At the temperature of 95 ℃，the injection of 0.3 PV SNBC solution with a mass concentration of 0.005% could improve the recovery rate by 15.8—20 percentage points under different permeability of 50×10^-3 —450×10^-3 μm² in the target oilfield. As a result，the SNBC oil displacement technology is suitable for enhanced oil recovery of high temperature and low permeability reservoirs in Henan oilfield.