Abstract: Brown seaweed is known as it contains an abundance of great potential bioactive compounds in the area of pharmaceuticals, food, and biomedical industries. Ecklonia cava is a brown seaweed widely distributed on the coasts of Korea and Japan which can be used as food ingredient, animal feed, fertilizer, and medicine. Ecklonia cava contains a variety of compounds including polyphenol, fucoidans, carotenoids, and phlorotannins. The paper reviewed the functional activities of active substances isolated from Ecklonia cava, focusing on the anti-inflammatory, anti-oxidation, anti-diabetic, anti-coagulant and anti-tumor activities of polyphenols and fucoidan. The research summarized the progress of current status and application of most active substances, and the development of Ecklonia cava industry was prospected, which provides a reference for the further research and development of Ecklonia cava active substances.