Abstract
In this study, we sequenced and determined the complete mitochondrial genome of Oncorhynchus keta and Oncorhynchus masou masou, which are the economically important fish species of China. They are circular molecule of 16,656 and 16,704 bp in size, containing 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs and a displacement loop region (D-loop). Oncorhynchus keta mitochondrial genome consists of A: 27.80%, T: 26.21%, G: 16.98%, C: 29.01%. Oncorhynchus masou masou mitochondrial genome consists of A: 28.20%, T: 26.82%, G: 16.52%, C: 28.46%. The total length of the 13 protein-coding genes was 11,420 and 11,415 bp.