The Neretva river basin is inhabited by many endemic species in Bosnia and Herzegovina, and Croatia. Some of these endemic species are not enough or even explored. Among them there are two fish species: which are poorly explored Macal Dace (Squalius microlepis) and Adriatic Rudd (Scardinius plotizza). The aim of this study was to determine length-weight and age of the fish, von Bertanlanffy growth, and to calculate the Fulton condition factor (CF). The emphasis of the thesis was on scales by which age structure and growth was determined. In addition to scales analysis, the data of total length (TL) and weight (W) of 51 Macal Dace of the Matica River and 55 Adriatic Rudd of the Deransko Lake were used. The maximum recorded values of total weight and length represent the highest recorded value in the current research for both types. Also, Macal Dace and Adriatic Rudd achieved high condition factor. In both studied species there was indicated positive allometric growth. In Macal Dace constant b was 3.10, while of Adriatic Rudd b was 3.25. By determination of the age structure of Macal Dace and Adriatic Rudd this work created the basis for further similar research.