Abstract: A series of HPSA hyperbranched surfactants were synthesized and then analyzed by infrared and elemental analysis. This paper aims to studied the influence of dosage of N-lauryl monoamido sulfo-succinic acid, pH value, electrolyte and temperature on the stability of emulsion from three different aspects: macroscopic phase separation, mesoscopic droplet size and microscopic interface film stability. The results showed that the emulsification performance increased first and then decreased with the increase of substitution degree. HPSA has a pH response, which is more hydrophobic under acidic conditions, and more hydrophilic under alkaline conditions and it can form a stable emulsion in a wide pH range (6-11). By compressing the double charged by Na at the concentration 0-1.5?105mg/L, the strength of the interface film formed by HPSA at the oil-water interface is increased, the zeta potential is lowered, and the stability of the emulsion is enhanced. The temperature mainly affects the molecular thermal motion of HPSA, which makes the collision rate of the emulsion formed by HPSA on the interface film increase and the stability decreases. The stability of emulsion is better below 120℃. Microscopically, the molecular structure of HPSA is rigid, which weakens the change of interfacial film caused by droplet collision. HPSA molecule is not easy to flow with the curvature of the liquid film during the collision of emulsion droplets. Hyperbranched surfactants self-assemble in aqueous solution to form micelle aggregates with different hydrophilic/lipophilic properties, which makes it has stronger ability of solubilizing and emulsifying crude oil