Abstract: ZY-M1505 is a negative- nonionic amphoteric surfactant aimed at Block Ming 15 Zhongyuan oilfield flooding. Relationship between surfactant concentration and interfacial tension, thermal stability and oil flooding performance of ZY-M1505 flooding surfactant were evaluated in laboratory and then field test was conducted. Experimental results show that under the formation conditions of Block Ming15, the injection water, formation water and surfactant solutions all can achieved to ultra-low interfacial tension, and have long-term thermal stability and a certain ability of oil displacement. Field test results show that the surfactant flooding enhances the efficiency of oil washing, and improve the test block development state. Production decreasing of this block was significantly reduced, and increasing oil effect is obvious.