Steam flooding can enhance greatly the heavy oil recovery. However, for single steam flooding, it is possible to decrease the steam sweep efficiency resulted by poor heavy oil development efficiency due to steam channeling and heterogeneity. This paper has designed an experiment of nitrogen foam-assisted steam flooding and studied the oil displacement efficiency of single steam flooding and foam-assisted steam flooding. The experiment result shows that the oil displacement efficiency of single steam flooding is 63.52%,while the foam-assisted steam flooding is 69.65%, which is higher than that of former. And, it is testified that the nitrogen foam-assisted steam flooding can dramatically improve the oil displacement efficiency. In addition, we have studied the injection parameter optimization of nitrogen foam-assisted steam flooding. The result is that 1:1 of gas-liquid ratio, 0.5% of foam agent concentration and lower water cut of foam injection time. This experiment demonstrates that nitrogen foam-assisted steam flooding can be used in high permeability formation to enhance oil displacement efficient, and obtain good heavy oil reservoir development.