Анотация: The genetic-biochemical analyses of two silurid species S. glanis and S. aristotelis are carried out. Eight enzyme and fourteen non-enzyme loci were investigated. The differences on the species level between S. glanis and S. aristotelis on some enzyme system (esterase - EST, malic enzyme - MEP, superoxide dismutase - SOD, 6-phosphogluconate dehydrogenase - 6-PGDH and malate dehydrogenase - MDH) and isoelectric focusing (IEF) of general muscle proteins (PROT) could be used for control of its posterities. The low genetic distance between the species examined, show that these species, belonging to one and the same Genus