The effect of low-dose irradiation and of age on the radiosensitivity of human lymphocytes was studies in two groups: control (67 people) and exposed to uncontrolled low-dose irradiation in past (165 people). Radiosensitivity of lymphocytes was estimated by the level of chromosome aberrations induced in vitro by gamma-radiation Cs137 at the dose 1.5 Gy. In exposed children the frequency of induced chromosome aberrations was higher and in the exposed adults--lower in comparison to the coresponding controls. To investigate an age response of the number of chromosome aberrations three statistical approaches were used: the correlation analysis of individual data, the correlation analysis of means for 10-years intervals, the comparison of 3 age groups. In control group no significant alteration in the level of induced chromosome aberrations with age was found. However the significant negative correlation between these two parameters was revealed in exposed group, which likely is due to the opposite direction of differences in radiosensitivity of exposed children and adults from the corresponding controls.