Objective — to study of the impact of various adverse factors on spermatogenesis and the level of free radical oxidation in the ejaculate. Material and methods. The study involved 40 men of reproductive age married for 2—3 years with no children in marriage. The patients were divided into 4 groups according to the nature of adverse factors: oil and gas industry workers, radar and broadcasting employees, creative workers, and unemployed poor people. The control group was composed of physically healthy men of comparable age with children in marriage. The MDA level in the ejaculate, as well as morphological and kinetic parameters of spermatozoa was determined. Results. Adverse environmental factors provoked lipoperoxidation intensification. The most toxic agents with respect to fertilizing properties of ejaculate appeared to be natural and associated petroleum gases, provoking decline in sperm concentration and motility in the oil and gas industry workers. The essential changes in sperm morphology in the radar and broadcasting employees took place due to mechanical damage of microwave radiation. The supression of spermatogenesis in the creative workers was of complex nature due to the enhanced dynamics of free-radical oxidation, as well as the participation of central regulatory mechanisms. Spermatogenesis in the unemployed poor men with hyponutrition was caused by the lack of biological resources necessary to maintain spermatogenesis and provide reliable antioxidant protection. Testosterone and luteinizing hormone levels were decreased in all men exposed to adverse environmental factors with exception of the radar and broadcasting employees. Conclusion. Thus, the impact of various adverse factors was accompanied by lipoperoxidation intensification in the ejaculate, which correlated with the worsening of morpho-kinetic indexes of spermatozoa and decreased sperm concentration.