Two grams of Sargassum powder, through the combination of sonication and microwave in 160ml pure water, yielded 91.79 mg of polysaccharides and 23.54 mg of total polyphenol; 76.81 % of DPPH free radicals were removed. Also, 0.1% liposomal Sargassum solution mixed with xanthan gum powder, through 4℃/45℃ high-low temp cycles for 84 hours, formed a homogenous (no stratification) colloid of particles, and the diameter of these particles went from 232±7.36 nm to 310.0±13.92 nm. When liposome-encapsulated Sargassum was applied on the skin for 28 days, it increased moisture retention by 31.39%, elasticity by 7.62 % and reduced melanin by 9.18%. This study suggests that liposome-encapsulated Sargassum has an application for skin care.