Abstract: The nutrients and nutritive value of Arapaima gigas fillet were determined.The results showed that the protein and fat in the fresh muscles were 16.5% and 6.8%,respectively.The total content of 18 amino acids was 54.76%(dry weight),while 37.6% of which was the 8 essential amino acids.The ratio of essential amino acids to non-essential amino acids was 58.91%.The essential amino acids index was 65.7,with the first and second limiting amino acid being Met and Trp,respectively.The content of 4 flavoring amino acids was 22%.It contained 8.6% DHA and EPA.The unsaturated fatty acid made up 55.8% of the total fatty acids.The contents of minerals and trace elements were high,particularly,Ca(i.e.,3367 mgkg-1).