Genotype segregation of parents livestocks (G₀ generation)and their offspring (G₁ generation)of 6 Litopenaeus vannamei families was analyzed on basis of 7 microsatellite DNA markers.In addition, heterogeneity analysis for pairwise comparisons of expected heterozygosities (H_e) of all loci between G₀ and G₁ was carried out and genetic differentiation through F-statistics at each locus in G₁ population was expected to monitor genetic variation in Litopenaeus vannamei breeding. The results showed that 44 alleles were detected in total across 7 loci assayed,mean number per locus,mean expected heterozygosity and mean polymorphism information content of G₀ generation were 6.14, 0.786 and 0.709 respectively, and those of G₁ generation were 6.27, 0.733 and 0.695 respectively. The combined exclusion probability of 7 microsatellite markers arrived at 0.99 and could seperate all 6 families with known parent. Heterogeneity analysis for pairwise comparisons of expected H_e of all loci between G₀ and G₁ indicated that H_e of G₀ was significantly higher than G₁(P<0.01). F_ST of G₁ per locus ranged from 0.270 3 to 0.465 4 and average was 0.358 4 which meant that genetic differentiation in its subpopulation was high. The UPGMA analysis based on six families genetic distances showed all individuals of G₁ generation could be classified into 4 categories.Similarly to families C and D, families A and B sharing father had high similarity coefficient and clustered together, family E and F were assigned into another group respectively.