Abstract: Tight sandstone gas reservoirs in western Sichuan region of low porosity and low permeability, pore structure is poor, high clay content,serious water locks and formation pressure drops in the middle and later stage of development, resulting in easy damage in the reservoir fracturing process and bad effect of back flow after pressure. Therefore, multifunction surfactant is added in the fracturing fluid, which shows many advantages as good foaming properties, low surface tension, and good expansion performance. Greatly reducing the fracturing fluid damage, and promoted the back flow of fluid. The fracturing fluid field application shows apparent effect as backflow rate and speed have been significantly improved as well as the production.