A new low-tension foam flooding system is developed for high-temperature and high-salinity reservoir using molecular simulation and in-home experiments. Under the conditions of 80 °C, the foam volume maintained at 200 mL and half-life >5 000 s, implying that the foam system has great foaming capability and foam stability. A one-month single-well test with low-tension nitrogen foam flooding is carried out at Shengtuo field on August 30, 2011. The foaming capability and foam stability of foam system under different conditions are investigated. The plugging ability for high-permeability streaks is examined as well. The injection mode and gas/liquid ratio are optimized. The cumulative injection of foaming agent is 2 087 m3. The average water cut of 3 influential producers decreased from 98.5% to 97.8%. The average fluid production is stable and oil production increases from 6.3 to 9.2 t/d. According to the perfor?mance of injectors and producers and the variation of injection profile, the low-tension foam system can form stable foam and exhibit good blocking efficiency for high-permeability streaks. The gas-liquid mixed injection can improve percolating resistance and plugging ability. The optimal gas/liquid ratio under test condition is 1∶1.