Industrial usage of different macro algae has grown exponentially during the last decade. Nutritional applications for human feeding and multiple therapeutic are their main important exploitation. This work is aimed at providing information on a species of Sargassum so as to promote this alga to be potentially profitable from biotechnology and commercial perspectives, and also benefit public health. The proximate composition, total phenolic content, total antioxidant activity, alginic acid yield of brown seaweed, Sargassum ilicifolium were studied. The seaweed was high in carbohydrate (33.38-40.21% DW) and low in lipid content (0.17-0.04% DW). Total phenolic content and total antioxidant activity of this seaweed species are 28.66±3.05 mg /g and (36.66±9.86 mg /g respectively. This seaweed showed (12.6-15.0%) alginic acid yield which can be used as immune- stimulant in food and feed.