Genetic diversity of 8 wild stocks of red swamp crayfish (Procambarus clarkii) from Tonglu (TL),Taihu Lake (TH),Hubei (HB),Jiangxi (JX),Hongze Lake (HZH)，Chongming (CM),Guangxi (GX),and Haiyan (HY),were investigated using 10 microsatellite DNA loci.In these 8 populations，the observed heterozygosity (Ho)，expected heterozygosity (He),and polymorphism information content (PIC) of these populations ranged from 0.525 7 to 0.740 0,from 0.623 8 to 0.743 4,and from 0.420 9 to 0.684 0,respectively,indicating a high level of genetic diversity.The highest and lowest genetic diversity were found in the Guangxi population and Taihu population,respectively.Then,genetic distance was calculated using the MEGA 4.0 software.And the genetic distance between HB population and TH population was the smallest,while that between CM population and JX population was the largest.