The study was carried out on the left tributaries of the Mures River (Mures lower gorge) in the spring of the year 2011. Some of the physico-geographical and hydrochemical parameters were determined. The aim of the study was to assess the state of fish communities in this region of the basin of Mures River, and also to highlight significant changes in fish communities, such as biodiversity, stocks, biological integrity. The biological material was collected by electrofishing from 9 sampling sites. Over the year 2011, 7 fish species were found, with an amount of 791 individuals and 5204,4 g. All of the 7 fish species are native species. We found that the numerical stock in sampling sites ranged between 1.14 and 200 indiv./100 m2 meanwhile the weight stock was between 3.84 and 2081.15 g/100 m2. Although a high value of the numerical stock is not always correlated with a high value of the weight stock, in Valea Salcivei, upstream Salciva we found the highest value for both of numerical and weigh stock and it is due to the large-size species (chub).
