Seafood processing activity causes production of considerable amount of waste/by-products and discards, resulting in negative economic and environmental impacts. Management of sustainable utilisation of seafood resources is essential to avoid environmental problems and provide resource sustainability. Fishery discards and seafood by-products are rich in bioactive compounds, including omega-3 long-chain polyunsaturated fatty acids, amino acids, peptides, enzymes, gelatine, collagen, chitin, vitamins, polyphenolic constituents, carotenoids etc. Fish discards are also regarded as a good and cheap material for biodiesel production. These high value added compounds have potential applications in many industrial sectors including food, nutraceuticals, pharmacology, medical, agriculture, depending on their functional and structural characteristics. This review will provide a comprehensive information on recent approaches for valorisation of bioactive compounds derived from discards and seafood by products. Many studies on the bioactive compounds derived from fishery discards and processing by-products were carried out in terms of nutritional and functional properties. Further studies on bioavailability of nutrients, yield, physicochemical properties, interaction with other ingredients, together with innovative approaches for extraction methods and legislation and safety issues should be considered