PCR and DNA sequencing technology were used to compare the DNA sequence of mitochondrial control region of 3 Channa argu populations to study the structure and the genetic diversity.The result shows that the sequence length of the D-Loop region which was used for analysis is 905-908 bp.37 polymorphic sites were found in 104 sequences and 27 haplotypes were defined.Meanwhile,the control region was analyzed,including terminal associated sequence,central conserved domains and conserved sequence block domains.The haploid type diversity(H_d),nucleotide diversity(P_i)and the average number of nucleotide differences(k)of 3 geographical populations were 0.875,0.003 27 and 2.939 respectively.Average Kimura double parameters of genetic distance between populations,genetic differentiation index(F_st),gene exchange value(N_m)and Analysis of Molecular Variance(AMOVA)all indicated that 3 populations of C.argu have high genetic differentiation.The Baiyangdian population and Pinyuan County population had certain gene exchange.