Most of the human chromosomal abnormalities seems to be of a germ-cell origin. Human oocytes are difficult to obtain and to handle, so most of the studies has been performed on male gametes. Genetic status of spermatozoa may be critical for human reproduction as well as wellbeing of fetus. The ability to identify and to characterize chromosomal aberrations in human sperm would lead to understanding of the mechanism causing chromosomal abnormalities and to approach possible preventive strategies. The aim of this paper was to present current data concerning the chromosomal aberations in human spermatozoa. Presented overview strongly underlines the importance of genetic investigations of male gametes.