At present, with the increase of water injection multiple rounds of tight oil in Santanghu Oilfield, the efficiency of oil-water replacement has been dramatically reduced. In order to study suitable surfactants and improve the imbibition recovery of tight oil, Nuclear magnetic resonance (NMR) technology and imbibition experimental device of quantitative measuring the viscous oil were used to investigate the mechanism of tight oil core imbibition and the effect of surfactants Tween 20, Tween 80 and WLW（Sodium Secondary Alkyl Sulfonate +Coconutt Diethanol Amide） solution on recovery by tight oil imbibition. The results show that the reason for the retention of imbibition and oil adherence on rock surface in transition pore is that the capillary force weakens and the flow resistance cannot be overcome as the imbibition proceeds; Surfactants can disperse and emulsify oil droplets, reduce the interfacial tension between oil and water, improve the wettability of rocks, and reduce adhesion power reduction factors, thereby reducing the resistance of flow, improving the power of imbibition or improving the difference value between capillary power and resistance of imbibition, so improving oil-water displacement efficiency, and achieving the purpose of surfactant improving imbibition recovery. Through this research, the understanding of surfactant on improving imbibition recovery is deepened, which will provide experience for efficient development of tight reservoirs.