Abstract This paper aims to develop the microemulsion preparing with microbial surfactant rhamnolipids for cosmetic applications. The optimized microemulsion formula base was obtained by drawing the pseudo three-phase diagram of the rhamnolipids-squalane-glycerol-water microemulsion system and measuring the physical and chemical properties. On this basis, through the determination of physical and chemical properties, stability analysis, subjective evaluation and efficacy evaluation, the rhamnolipids microemulsion with the best formula of microemulsion essence were obtained. Results showed that the obtained O/W microemulsion was clear, transparent. The particle size of the microemulsion was about 44 nm, and the Zeta potential was about -31 mV. Rhamnolipid microemulsion essence had good stability and could significantly increase the moisture value of the skin and improve skin elasticity. This result showed that rhamnolipids were suitable for preparing microemulsion carriers for cosmetics.
