This paper presents the activity concentrations of Po-210 and Pb-210 in 15 different commercial fish species collected around Gokceada Island (northern Aegean Sea) in 2016. The distribution of Po-210 and Pb-210 was investigated in fish tissues and significant differences (P<0.05) in radionuclide concentrations were noted between muscle, gills, and liver in each species. Po-210 activity concentrations in tissues were systematically higher than those of Pb-210 and the average values of Po-210/Pb-210 concentration ratios were calculated at 6.6 +/- 1.5, 8.4 +/- 3.2, and 10.2 +/- 1.6 in muscle, gills, and liver, respectively. The annual effective dose to consumers through Po-210 ingestion with fish filet averaged 62 mu Svyear(-1) (range 5.5-160 mu Svyear(-1)). This effective dose is in the range of natural radiation doses reported worldwide for humans through ingestion of sea food.