Marine algae can be classified into two major groups, microalgae and macroalgae; blue-green algae, dinoflagellates and bacillariophyta are microalgae, while green, brown and red algae are classified as macroalgae. The cosmetic industry has already exploited the world of macroalgae; however, the information relevant to microalgae is still scanty. Among the active ingredients extracted from microalgae, polysaccharides demonstrate greater potential for use in cosmetic ingredients. Chlorophylls are green pigments which can easily extracted from microalgae and used to mask odors in the cosmetic industry. Macroalgae are also recognized as promising source of vitamins, minerals and trace elements. Secondary metabolites such as phenolic compounds present in macroalgae do not directly intervene in primary metabolic processes; however, protection mechanisms therein, namely against oxidative stress or ultraviolet cytotoxic effects.