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The results of an assessment of the activity concentrations of Sr-90 and Cs-137 absorbed dose rate in fish inhabiting the Chornobyl Exclusion Zone (CEZ) over the period 2010-2025 are presented herein. The studies were carried out in lakes of western and northwestern radioactive traces that are most contaminated with radionuclides - Azbuchin, Vershina, Glyboke, Yanovsky backwater, as well as in various parts of the Chernobyl NPP cooling pond (CP) and the Pripyat River within the CEZ. The activity concentration (AC) of Cs-137 was measured using a γ-spectrometry complex (Mirion Technologies-Canberra, Japan). The AC of Sr-90 was determined using a low-background alpha-beta radiometer UMF-2000 and beta radiation energy spectrometer SEB-01-70. The highest levels of the AC of the main dose-forming radionuclides were noted for fish from lakes Azbuchin, Vershina and Glyboke: Sr-90 – 2030-148570 (on average 15960); Cs-137 - 930-31859 (4660) Bq/kg. In the Yanovsky backwater, the concentration of Sr-90 and Cs-137 in fish was, respectively, within the range of 583-8220 (1520) and 340-6040 (1395) Bq/kg. In the CP, the AC of Sr-90 and Cs-137 was, respectively, 40-359 (119) and 540-11270 (2473) Bq/kg. The lowest concentration of radionuclides, among the studied water bodies, was noted for fish from the Pripyat River within the CEZ: Sr-90 – 2-121 (33); Cs-137 – 5-293 (71) Bq/kg. The prey fish species of the studied lakes were characterized by AC of 90Sr within the range of 4050-148570 (21328), and Cs-137 – 1018-31859 (3749) Bq/kg, while in predatory fish the AC of Sr-90 was 2030-31622 (7994), and 137Cs – 930-22044 (6228) Bq/kg. The activity concentration of Sr-90 in the fish of the Yanovsky backwater did not exceed 860–4580 (1900) Bq/kg for prey species, and 583-8220 (1140) Bq/kg for predatory ones; the activity concentration of Cs-137 in prey species and ichthyophagous fish was, respectively, within the range of 340-3400 (784) and 1030-6040 (2001) Bq/kg. Thus, the AC of Sr-90 in prey fish of the stagnant water bodies of the CEZ was 1.6–1.7 times higher than in predatory species, while Cs-137 was 2.5-2.6 times lower. Among the studied fish of the CEZ, the highest concentration of Sr-90 was noted for the common rudd and Prussian carp. Different fish species in descending order of average AC of Sr-90 in the CEZ water bodies form the following series: Prussian carp > common rudd > roach > tench > bream > bleak > asp > perch > pike > pike-perch > wels catfish, and in descending order of Cs-137 - perch > pike-perch > pike > asp > wels catfish > bleak > rudd > Prussian carp > roach > bream. The highest dose rates in the water bodies of the CEZ were observed in benthic fish species, including tench, Prussian carp, and European wels catfish, whereas the lowest dose rates were recorded in pelagic species such as bleak and sabrefish. Among the investigated water bodies, the greatest absorbed dose rates were registered in Lakes Vershina, Glubokoe, and Azbuchin for tench (53.1-130.8 μGy/h) and Prussian carp (36.3-110.4 μGy/h). In contrast, absorbed dose rates for fish inhabiting the Yanovsky backwater and the CP ranged from 2.30-15.21 and 6.04-31.30 μGy/h, respectively. Ichthyofauna from the channel section of the Pripyat River exhibited substantially lower dose rates, within the range of 0.06-0.13 μGy/h. This study was supported by the Ministry of Science and Education of Ukraine (Project No. M/09-2025).