Fisheries and aquaculture significantly contribute to global food and nutritional security by providing a crucial source of protein, essential nutrients, and income for millions of people worldwide. This chapter examines their multifaceted roles in meeting the dietary needs of a growing global population. Fisheries provide a substantial and accessible source of animal protein, essential fatty acids, vitamins, and minerals, contributing significantly to food security. Fish consumption is associated with various health benefits, including reduced risk of cardiovascular diseases and improved cognitive development. Aquaculture has emerged as a critical contributor to food security, providing a sustainable source of fish and seafood. It helps to meet the increasing demand for fish products while reducing pressure on wild fish stocks. Aquaculture also has the potential to enhance nutritional security by producing fortified and value-added products. Despite their contributions, fisheries and aquaculture face challenges such as overfishing, habitat degradation, and climate change. Sustainable management practices, technological innovations, and policy interventions are needed to address these challenges and ensure the sectors’ long-term viability. In conclusion, fisheries and aquaculture play a crucial role in enhancing food and nutritional security, offering significant opportunities to improve global health and well-being. Sustainable management practices and innovative approaches are essential to maximize their potential in meeting the food and nutritional needs of present and future generations.