Abstract: The nutritional composition in the muscle of Penaeus japonicus was analyzed and compared with that of some high-quality shrimps, crabs and fish. The results showed that the contents of flesh, water, crude ash, crude protein and fat in P. japonicus were 39.21%, 77.16%, 1.79%, 17.74% and 2.08%, respectively. Eighteen common amino acids were detected in the muscle of P. japonicus. In dry samples, the content of total amino acids (TAA) was 70.68%, in which the content of essential amino acids (EAA) was 23.25%. The essential amino acids index (EAAI) was 70.72, which was lower than egg protein standard but higher than WHO/FAO standard. According to amino acid scores (AAS) and chemical scores (CS), the first limited amino acid was Trp and the second limited amino acid Val. The content of five delicious amino acids (DAA) were 35.71% in dry samples. Meanwhile, nine saturated fatty acids (SFA), eight mono-unsaturated fatty acids (MUFA) and eight polyunsaturated fatty acids (PUFA) were also detected in the muscle of P. japonicus. The PUFAs in the muscle of P. japonicus accounted for 64.04% of total fatty acids. The contents of EPA and DHA were 1.70% and 10.92% of total fatty acids, respectively, and the contents of PUFA, EPA and DHA were higher than those in some shrimps and freshwater fish. The mineral elements Zn and Fe were abundant, and the contents of harmful elements such as Cd, Cr and Ni were low. Therefore, it is easy to conclude that Penaeus japonicus is a nutritious and delicious food.

Key words: Penaeus japonicus, muscle, nutritional composition, quality evaluation