To establish a molecular genetic marker for identifying different populations of Pelodoiscus sinensis,pomc gene was amplified by PCR and identified by RFLP using four restriction endonucleases including AccⅡ,BscBⅠ,AsuⅠ and TscⅠ.At the same time homology were compared and phylogenetic trees were constructed.The results showed that a 786 bp fragment was amplified from four P.sinensis populations.The relationship between Taiwan-introduced and Pelodiscus axenaria populations was closer and the relationship between Taihu Lake and Huanghe River population was closer.For AccⅡ digestion,the P.axenaria population carried two bands of 303 bp and 483 bp,while the other three populations carried only one band of 786 bp; for BscBⅠ digestion,Taiwan-introduced and P.axenaria population carried two bands of 351 bp and 435 bp,while the other two populations carried only one band of 786 bp; for AsuⅠ digestion,Taiwan-introduced and Huanghe River population carried two bands of 349 bp and 437 bp,while the other two populations carried only one band of 786 bp; for TscⅠ digestion,Taihu Lake and Huanghe River populations carried two bands of 349 bp and 437 bp,while the other two populations carried only one band of 786 bp.Combined application of the four restriction endonuclease could clearly identify the different population of P.sinensis at the molecular level.All results suggested that the pomc gene could be used as a molecular genetic marker for identifying different population of P.sinensis.