The purpose of the study was to establish the frequency of EEG abnormalities in mother and child when one of them has epilepsy. The incidence and type of EEG abnormalities were analysed in 2 groups: 33 epileptic children and their 31 healthy mothers, and 28 epileptic mothers with their 46 clinically healthy children. For illustration of data distribution in EEG the examined subjects were divided in both groups into mother-child pairs comparing the features of the records as well as morphological similarity of the curves in mother and child. It was found that the probability of abnormalities in the bioelectric activity of the brain is the same in a healthy child of an epileptic mother (67.3%) as in a healthy mother of an epilepitic child (51.6%). The frequency of EEG pathology was greater in daughters than in sons of epileptic mothers. Similarities in morphological patterns of EEG occurred in only 3 cases in mothers of epileptic children and in 8 children of epileptic mothers.