To investigate the composition of fat and fatty acid in 12 kinds of aquaculture products in Hainan Province. A total of 12 aquatic products were monitored in 8 breeding bases in Hainan Province, the edible parts were tested for fat and fatty acid. The content and composition of fat and fatty acid were analyzed. A total of 12 aquaculture products were monitored, including 6 freshwater aquaculture products and 6 mariculture aquatic products. The contents of crude fat and total fatty acid(TFA) ranged from 1.2 to 20 g/100 g edible and 1.0 to 15 g/100 g edible, and they were positively correlated(r=0.989, P<0.01). A total of 18-30 fatty acids were detected. Among them, 12 were saturated fatty acids(SFA), ranging from 0.34 to 6.4 g/100 g edible, mainly palmitic acid, eight were monounsaturated fatty acids(MUFA), mainly oleic acid. Ten were polyunsaturated fatty acids(PUFA), ranging from 0.28 to 2.6 g/100 g edible, It was mainly composed of linoleic acid(LA), docosahexaenoic acid(DHA), α-linolenic acid(ALA) and eicosapentaenoic acid(EPA). The composition of fatty acid in aquaculture products in Hainan Province is mainly unsaturated fatty acids(UFA), and most aquatic products are rich in n-3PUFA, and the ratio of n-6PUFA to n-3PUFA is less than 6, which has high nutritional and health value, and is beneficial to the nutritional diet balance of of population.