Abstract: Surfactant molecules will form an ordered structure at the oil-water interface to promote film formation at the interface. To clarify the effect of this molecular adsorption behavior on film formation at the oil-water interface and its micromechanisms is of great significance for establishing the analysis methods of stability and instability of oil-water emulsions in crude oil production and transportation. Using the sodium dodecyl benzene sulfonate (SDBS), a common anionic surfactant, as an example, and the moving plate wall surface to assign a shear flow field to the "crude oil-SDBS-mineral water" interface simulation system, in combination with the non-equilibrium molecular dynamics (NEMD) method, the paper reveals the effect of adsorption behavior of surfactant molecules on film formation at the oil-water interface in the shear flow field, and also explains the mechanisms by which shear velocity, temperature, pressure, and surfactant concentration affect the stability of film formation at the interface. The results show that the stability of film formation at the interface can be affected by the adsorption configuration of SDBS molecules, the hydrogen bonds formed between SDBS molecules and water molecules, and the diffusivity of oil oleic and aqueous phase molecules; applying shear stress is a process of instability to stability for the oil-water interface system, and the stability of film formation at the surface decreases with the increase of shear velocity; in the range of SDBS concentration of 0.15-0.70 mol/L, the thickness of the interfacial film increases from 1.43-2.13 nm under static working conditions to 2.74-2.93 nm under dynamic shear working conditions; the increase of temperature will destroy the hydrogen bonds formed between molecules, leading to interface instability, and the increase of pressure will shorten the length of hydrogen bonds formed between molecules, enhancing the strength of intermolecular interactions and being conductive to the stability of the interface.