Abstract: Intra-and inter-population genetic variation of grass carp, red common carp and common carp was analysed using random amplified polymorphic DNA (RAPD) markers. The RAPD patterns of grass carp (Ctenophoryngodon idellus) were remarkably different from those of common carp (Cyprinus carpio), and the inter-population average band sharing between grass carp and the two common carps (red common carp and common carp) were 0.2583 and 0.2394, respectively, and the cormsponding genetic distances between them were 0.9362 and 1.2277. However, the RAPD patterns of red common carp and common carp were very similar, with the average band sharing between them being 0.7162 and genetic distance 0.0947. The intra-population average band sharing of grass carp, red common carp and common carp were 0.8424, 0.7819 and 0.7928, respectively, average band frequency were 0.82,0.71 and 0.74, respectively, and the genetic variability were 0.18, 0.29 and 0.26,respectively.