Data about some genetic factors of male infertility are presented, and methods, which may be used for its diagnosing, are studied. Among genetic factors the following are distinguished: changes in the level of genes (mutations), chromosomes (chromosomal aberrations), and total DNA (chromatin dispersion and DNA fragmentation). As well as standard cytogenetic methods of investigation there are a number of molecular-cytogenetic methods like FISH (fluorescent in situ hybridization), TUNEL (Terminal uridine deoxynucleotidyl transferase dUTP nick end labeling), SCSA (sperm chromatin structural assay), SCGE (single cell gel electrophoresis), and SCD (sperm chromatin dispersion). The thorough study of the sperm of infertile men on several levels of organization let us assess the informativity of each method separately and together, and also develop an optimal algorithm of diagnostics with the aim to choose further tactics in the treatment of male infertility.