The authors have studied effective doses of internal and external radiation for 1992-1994 in the residents of Chernigov and Kharkov Regions of Ukraine, i.e. those who live in the zone of strict radioecologic control and in relatively ''clean'' zones, respectively. In 95% of the investigated residents of Chernigov Region Cs-137 activity in the organism was lower than 1500 Bq, maximum amount being 11 kBq. Conditioned Cs-137 effective dose of internal radiation did not exceed 250 microSv per year, in 96% of the investigated subjects it was less than 30 microSv per year. Mean amount of this radionuclide in the organisms of both adults and children aged 3-6 years residing in Kharkov Region was 90 and 6 Bq respectively, dose being 2 and 0.4 microSv per year. Sr-90 amount in the bone tissue decreases with the age and for the residents of Chernigov region it was 7-23 Bq/kg of bone, for the adultresidents of Kharkov region it was about 3 Bq/kg of bone. Mean effective dose of internal radiation due to Sr-90 incorporation for the residents of both Kharkov and Chernigov Regions was 0.7 and 1.9 microSv per year. Effective dose of exernal radiation for the residents of Kharkov Region has not changed since the Chernobyl accident. Total effective dose of external and internal radiation in various professional groups for the residents of Chernigov region increased by 80 microSv per year which makes up 14% of mean population dose in Ukraine.