The control region of mitochondrial DNA (13516-14619) is located between srRNA and $tRNA^{lle}$ gene in swimming crab, Portunus trituberculatus. The present study was investigated the genetic polymorph isms of the control region in samples of P. trituberculatus collected at coastal waters of the Yellow Sea in Korea. A total of 300 substitution and indel polymorphic sites were identified. In addition to SNPs and indel variation, a hypervariable microsatellite motif was also identified at position from 14358 to 14391, which exhibited 10 alleles including 53 different suballeles. When the hypervariable microsatellite motif was removed from the alignment, 95 haplotypes were identified (93 unique haplotypes). The nucleotide and haplotype diversities were ranged from 0.024 to 0.028 and from 0.952 to 1.000, respectively. The statistically significant evidence for geographical structure was not detected from the analyses of neighbor-joining tree and minimum-spanning network, neither. This result suggest that population of P. trituberculatus are capable of extensive gene flow among populations. We believed that the polymorph isms of the control region will be used for informative markers to study phylogenetic relationships of P. trituberculatus.