The purpose of this study was to investigate the genetic variety of A. eichwladi, as the local species of the Caspian Sea, using five microsatellite loci (including Reser10, Ca3, Llec-090, LeA-071, and Mfw17) in three sampling stations from Paulrood River, Roodsar. To do so, ninety samples in three sections of Paulrood River were collected. Of the five microsatellite indicators used for genetic evaluation in the present study, only three showed significant results. Analysis of the genetic variety data revealed that the average amount of observed heterozygosity (H₀) equals to 1. In addition, the mean of expected heterozygosity (H_e) is 0.755 among these three stations. Also, the average observed Allel in each genetic station is equal to 5.55 and its range was between 4-8 Allels in genetic stations. The average number of effective Allels (N_e) at the level of station was calculated as 4.276 for these three areas. In this investigating genetic differentiation, Fst and Rst were obtained 0.06 and 0.066 respectively, that indicating low genetic differentiation among the samples. All of the samples showed significant deviation from Hardy-Weinberg equilibrium mostly due to the heterozygosity deficiency. The number of Alleles and observed (H_o) and expected (H_e) heterozygosity was 4-8 (the average of 5.55) and 1.00 and 0.755 respectively, higher than the amount reported for fresh water fish. Also, analysis of molecular variance revealed the most of the observed diversity was among populations (95%)
and there is low diversity within the populations (5%). Results indicated that A. eichwldi has acceptable Allelic richness and considerable genetic diversity in Paulrood River