Within serological surveys 2001, prevalence of markers of hepatitis viruses A (anti-HAV), B (anti-HBc, HBsAg, anti-HBs) and for the first time also C (anti-HCV) was investigated. Sera were collected in 2001 and tested by respective kits AxSYM, Abbott. HAV: 2,623 sera were tested for the presence of anti-HAV antibodies. Comparison with serological surveys of 1984 and 1996 revealed again shifts of the age prevalence curve for anti-HAV antibodies towards higher age groups corresponding to time intervals between epidemiological surveys. High prevalence rates of anti-HAV antibodies (more than 20%) were only found for the population age groups who lived in the period of high incidence of VHA, i.e. up to 1965. The prevalence of anti-HAV antibodies increased by about 5-10% in the population under 20 years of age, the increase being significant and assumingly attributable to vaccination against VHA, and remained the same as in 1996 in the age group 20-29 years. HBV: 2,568 sera were tested for the presence of anti-HBc antibodies and 76 reactive specimens were further tested for the presence of HBsAg and anti-HBs antibodies. The prevalence of anti-HBc antibodies continuously increases with age. The total prevalence of anti-HBc antibodies calculated for the Czech population is 5.59% compared to 6.95% recorded in 1996. The calculated prevalence rate of HBsAg is 0.56% and that of anti-HBs antibodies is 3.99% for the non-vaccinee population. HCV: The prevalence rate of anti-HCV antibodies was 0.2% with 6 out of 2,950 sera testing positive. Age dependence could not be assessed because of the small number of positive persons. HCV infection is known to afflict high-risk groups, likely to escape a general serological survey, rather than the normal population.