Abstract: Compared with polymer flooding, alkaline/surfactant/polymer(ASP) flooding has higher recovery efficiency, and technology is more complicated. There are 83×10⁸ tons of the reserves suitable for ASP flooding; only for Daqing oilfield, there are about 14×10⁸ tons reserves that can be produced by injecting ASP solutions. The potentialities are great, but commercial production of ASP flooding doesn't realize for there are still many technical hurdles not be effectively spread. Based on the study and practice in ASP flooding for many years, formula systems of ASP flooding were developed, break through the technical limit that the crude oil with low acid value is hard to achieve ultralow interfacial tension in Daqing oilfield. The alkyl benzene sulfonate surfactant was developed, and commercial production of the surfactant has been realized. Meanwhile, available well pattern, well space, layers combination and injection parameters are also determined. The related key technologies such as lifting technique of scale control, the treatment of produced fluids have been gained, which can satisfy the needs of ASP commercial production. Field application results show that oil recovery by ASP system can be over 20% and 10% higher than water and polymer flooding, respectively. Being as a key alternative technology for Daqing oilfield's sustainable development, the industrial promotion of ASP flooding is ongoing, and this technology can provide technical support for other oil field development of high water cut stage and efficient development of continental sandstone oil field.