To assess the level of the energy metabolism in the development of salmon Salmo salar Linnaeus, 1758 (Salmonidae) from the Zolotitsa River (arkhangelsk region), the activity of enzymes оf aerobic and anaerobic metabolism (cytochrome c oxidase, COX, 1.9.З.1, lactate dehydrogenase, LDh, EC 1.1.1.27) and carbohydrate metabolism (glucose-6-phosphate dehydrogenase, G6PDh, EC 1.1.1.49, glycerol-3-phosphate dehydrogenase 1 GPDh1, EC 1.1.1.8, aldolase, ес 4.1.2.13) was studied in white muscles and liver of juveniles aged 0+, 1+, 2+ and 3+. age-related multidirectional changes were detected in the activity of the enzymes of aerobic and anaerobic energy metabolism in muscles. Muscular COX activity was high in parr at 0+, 1+, 2+ age, and decreased on the fourth year (3+ parr). The activity of LDh and aldolase in muscles was high in individuals of older groups. age-specific differences in the activity of enzymes in the liver, namely high activity of LDh and GPDh1 in third-year parr (2+), probably reflect changes in the involvement of carbohydrates in biosynthetic processes. These results were analyzed in comparison with those obtained previously for salmon parr from the Indera River (Kola Peninsula). There was a higher activity of LDh in muscles in the first and second years, and lower levels of muscular and hepatic COX and aldolase activities in all age groups from the Zolotitsa River compared to fish from the Indera River. The revealed differences in the activities of all the studied enzymes of energy and carbohydrate metabolism in salmon from the Indera and the Zolotitsa, as well as in their weight, are directly related to the different habitat conditions (foraging, hydrological) in these rivers.