Abstract: The phenomenon of channeling flow exists in steam flooding development, which seriously affects the development effect. While the thermal foam composite flooding can effectively improve the development effect of steam flooding. At present, some heavy oil fields in Bohai have the right conditions to steam drive after multicycle huff and puff. In this paper, oilfield M in Bohai is taken as an example, the mechanism of improving the development effect of steam flooding by foam was analyzed through 2D visualization experiment. And on this basis, the adaptability of the thermal foam flooding in this oilfield is studied through reservoir adaptability research. The results show that thermal foam has a certain sealing ability under the existing geological reservoir conditions, and under the condition of high temperature injection, increasing the temperature resistance of foam is of great significance for enhancing oil recovery of thermal foam composite flooding. Compared with single steam flooding, thermal foam flooding can improve oil displacement efficiency by about 30.0%.