the Ⅱ reservoir of heavy oil which is a deep buried heavy oil field with active edge and bottom water and high viscosity and so on, almost is in the middle and later stage, however, there are not any effective replacement processes currently. To solve these problems, the mechanism of steam flooding adding urea and foaming agent was studied with the physical simulation. In the experiment, the concentration of urea solution was 25%, the concentration of foam solution GFPA-4B and viscosity reducer DVB-107 was 0.5%, respectively, the permeability measured by water flooding of the sand-pack was 1.83~2.16 μm², the flooding rate was 3.6 mL/min. The results showed that urea solution could significantly improve the displacement efficiency , the cumulative displacement efficiency of the hot water+urea displacement, hot water+urea+foam solution displacement, hot water+urea+foam solution+viscosity reducer displacement was increased by 8.13%, 16.67% and 21.27%, respectively, compared to that of hot water displacement. The displacement efficiency of steam displacement section was also improved by 3.49%—9.41%, the cumulative displacement efficiency of the steam+urea displacement, steam+urea+foam solution displacement, steam+urea+foam solution+viscosity reducer displacement is increased by 3.49%、5.31% and 9.41%, respectively, compared to that of steam displacement. Besides, that the mechanism of steam displacement adding urea and foam solution was studied.