Abstract: We evaluated the nutritional components in back muscles of three kinds of skipjacks (Katsuwonus pelamis, Sarda orientalis and Auxis thazard). The results showed that: 1) the crude protein contents of three kinds of skipjacks were 22.86%~24.65%, while crude fat contents were only 1.41%~2.51%. Minerals were abundant in their back muscles. 2) Seventeen kinds of fatty acids were detected in K.pelamis and S.orientalis, while 23 kinds in A.thazard. The ratios of ∑PUFA/∑SFA were 1.17, 0.93 and 1.14, while the ratios of n-6/n-3∑PUFA were 0.07, 0.04 and 0.11, respectively. The content of poly-unsaturated fatty acids in back muscle of K.pelamis was 38.98%, higher than 33.64% of S.orientalis and 37.89% of A.thazard. 3) Essential amino acids content and essential amino acids index (EAAI) of S.orientalis were 35.10% and 0.90, respectively, higher than 33.95% and 0.89 of K.pelamis, and 32.51% and 0.89 of A.thazard.