The objective of this study was to determine the frequency of tooth caries and periodontitis affecting the athletes of different sports by means of molecular PCR-diagnostics. Materials and methods. The frequency and extent of oral tissue lesions were determined in 98 athletes taking up different sports with the use of molecular diagnostic methods in conjunction with the evaluation of traditional hygienic measures, the severity of tooth caries, inflammation, and bleeding. Results and discussion. The study demonstrated that PCR-diagnostics makes it possible to detect pathological changes in the oral cavity of most patients at the early stages of their development. It provides a basis for the timely sanation, rehabilitation, and treatment of the athletes and thereby allows them to maintain the top competition form and achieve excellent results.