We reviewed potential antioxidant and antivirus activities of brown algae. It’s known as Phaeophyceae, a plant-like protists and commonly found at the bottom of waters, especially in cold regions. Thousand types of brown algae have been identified. It is widely used as food and medicine ingredients, to use as natural nutrition addition and treatment for many diseases. Brown algae is a source of bioactive compounds because it is able to produce secondary metabolites that vary with extensive biological activity, including as an antioxidant to stop the chain reaction of free radicals. There have been many studies that prove that brown algae has antioxidant and antiviral activity. However, every species of brown algae and its thallus parts may have different levels of antioxidant and antiviral activity. The highest antioxidant was found in the apical of thallus, getting down to basal the antioxidant activity become lesser.