Abstract: 1 141-bp sequence of mitochondrial DNA cytochrome b gene of 23 individuals from 2 populations of Siniperca roulei collected in Duchang of Yangtze River and Jianou of Minjiang River was sequenced. 15 variable sites including 7 parsimony informative sites defined 13 haplotypes, the global haplotype diversity (Hd) and nucleotide diversity (Pi) were 0.933渊依 0.030冤and 0.00241渊依0.030冤respectively, indicating a pattern of high haplotype diversity and low nucleotide diversity. The significant negative values of neutral test of Fu爷s Fs and the unimodal mismatch distribution pattern revealed a historical population expansion deduced at about 60 000 years ago. With the intertwined haplotypes of various geographic populations in Neighborjoining and TCS tree, the Fst and Nm between two populations were 0.06667 and 3.5 respectively, 95.17% genetic variation occurred between populations was much higher than 4.83% genetic variation occurred in populations by AMOVA analysis, indicating that no obvious genetic differentiation was found and they could be protected as a single management unit.