The brown algae (Phaeophyceae), which belong to the protista realm, have been consumed by humans in various fields for many years. Research has shown that brown algae are considered to be rich sources of bioactive compounds, which are highly beneficial to health and have excellent nutritional value. Polysaccharides are the main components of brown algae; their different structures allow for physical and chemical properties that help regulate many biological activities such as antibacterial, antioxidant, prebiotic, antihypertensive, antidiabetic, antitumor and anticoagulant activities. As technology progresses, we see algas being used in many fields, including biomedical engineering. In this study, we will look at the uses of alginate, the main polysaccharide component in brown algae. We will provide examples of the importance of their structures for health, their use in medicine, their applications in tissue repair and in the pharmaceutical industry in detail.