As　the　market　size　of　the　cosmetics　industry　increases,　the　safety　and　effectiveness　of　new　products　face　higher　requirements.　The　marine　environment　selects　for　species　of　micro-organisms　with　metabolic　pathways　and　adaptation　mechanisms　different　from　those　of　terrestrial　organisms,　resulting　in　their　natural　products　exhibiting　unique　structures,　high　diversity,　and　significant　biological　activities.　Natural　products　are　usually　safe　and　non-polluting.　Therefore,　considerable　effort　has　been　devoted　to　searching　for　cosmetic　ingredients　that　are　effective,　safe,　and　natural　for　marine　micro-organisms.　However,　marine　micro-organisms　can　be　difficult,　or　impossible,　to　culture　because　of　their　special　environmental　requirements.　Metagenomics　technology　can　help　to　solve　this　problem.　Moreover,　using　marine　species　to　produce　more　green　and　environmentally　friendly　products　through　biotransformation　has　become　a　new　choice　for　cosmetic　manufacturers.　In　this　study,　the　natural　products　of　marine　micro-organisms　are　reviewed　and　evaluated　with　respect　to　various　cosmetic　applications.