Discovery of genetic variants of the HFE gene has made it possible to screen for hereditary hemochromatosis. However, genetic screening raises ethical, legal, social, and psychological questions, which need to be addressed. To assess the psychological impact on individuals undergoing genetic screening for hereditary hemochromatosis and to determine the effects of providing different levels of information to the participants. Male residents, aged 30-50 years (n = 10,993) were invited to a genetic screening for hereditary hemochromatosis. Carriers of the gene variants H63D, S65C, and C282Y were offered additional biochemical screening using serum ferritin and transferrin saturation. Psychological factors were evaluated through questionnaires before and after genetic and biochemical screening. According to genotype, participants were divided into three groups with different risks profiles for having/developing clinical hemochromatosis (at-risk, uncertain risk, no risk). Before completion of the questionnaires, 929 participants received only genetic information and 366 received both genetic and biochemical information. At-risk participants receiving only genetic information generally displayed negative reactions to the test result, whereas participants receiving both genetic and biochemical information were more satisfied and had fewer negative psychological reactions to the test result. Genetic screening is more readily accepted by subjects when genetic information is supported by biochemical measurements, especially in participants with a risk of clinical disease.