The present invention relates to a nanoemulsion comprising an oil layer comprising imidazoquinoline-based toll-like receptor 7 or 8 agonist and oil, and a use thereof as an adjuvant and vaccine. According to the present invention, it is possible to provide a vaccine adjuvant in the form of a nanoemulsion that can dissolve an insoluble imidazoquinoline-based material in oil using a dispersion helper and disperse the oil solution easily and reproducibly in a water-soluble manner.
