Numerous by-products from the wastes of marine items can be obtained and utilized in a wide range of sectors. The by-products obtained from cephalopod wastes are evaluated and used in various industries (such as food, medicine, and agriculture) by evaluating the wastes of the head, skin, intestines, ink, etc., much like all other wastes derived from marine goods. Because these by-products are rich in nutrients and contain biological substances, they are anticipated to be improved in several industries. Additionally, it should be stated that research to produce financial gains will be funded and that the by-products of these marine things will be acquired. In particular, this study investigates the synthesis of antioxidant and antibacterial agents, the extraction of bioactive components and their use as food additives, the synthesis of gelatin and peptides from cephalopod by-products, the impact of cephalopod by-products on extending shelf life, and the health risks and benefits of cephalopod by-products.