National rates of aquatic food consumption in Pacific Island Countries and Territories are among the highest in the world, yet the region is suffering from extensive levels of diet-related ill health. The aim of this paper is to examine the variation in consumption patterns and in nutrient composition of aquatic foods in the Pacific, to help improve understanding of their contribution to food and nutrition security. For this examination we analysed nutrient composition data and trade data from two novel region-specific databases, as well as consumption data from national and village level surveys for two Melanesian case studies, Vanuatu and Solomon Islands. Results demonstrated that consumption depends on availability and the amount and type of aquatic food consumed, and its contribution to nutrition security varies within different geographic and socio-demographic contexts. More data is needed on locally relevant species and consumption patterns, to better inform dietary guidelines and improve public health both now and into the future. Advice on aquatic food consumption must consider the nutrient composition and quantity of products consumed, as well as accessibility through local food systems, to ensure they contribute to diverse and healthy diets.