The level of antibodies was tested in 9 age groups since 6 years up to over 75 years of age for H and N of influenza A(H1N1), A(H3N2) and B in epidemic season 1990/91. The highest GMT were found in all age groups for H3-A/Shanghai/16/88, much lower for H1-A/Taiwan/1/86. The titers were almost the same in all age groups excluding 6-8 years where GMT was much higher. The lowest titers were found for hemagglutinin of B/Yamagata/16/88 and different in different age groups. The highest GMT of neuraminidase were found for N2 in group 41-50 years old, in other groups were different. GMT for N1 were differentiated, but in 51-64 years old group was 3.5 times higher in comparing to the lowest value. For B neuraminidase the titer of antibodies was the highest in 31-40 years old group, and the lowest for 41-50 old people.