Abstract: The complete sequences of cytochrome b (Cyt b)genes in Pseudosciaena crocea and Scioenops ocellatus, and the partial sequence of cytochrome b (Cyt b) gene in Miichthys miiuy were amplified using PCR technology. The PCR products were sequenced directly. 1 140 bp fragments of Cyt b genes in P.crocea and S.ocellatus, and 1 125 bp fragment of Cyt b gene in M.miiuy were obtained. Comparing obtained sequences, the comparability similarity of three sequences was 91.49%. Information of the base composition and the mutation sites were obtained. The difference of three sequences was obvious. The results contributed not only genetic data to economic utilization of three species but also scientific basis to analysis of genetic diversity in China Sea. Moreover, molecular phylogenetic tree of the Cyt b DNA sequences in the three species was reconstructed with the NJ method based on the inherited distance and the result showed that the inherited distance between the M.miiuy and the S.ocellatus was small.