The study of the relationship between the speed, stability, and accuracy of sensorimotor reactions (SR) and body com- position (BC) is relevant for sports science, physical training, military affairs, and rehabilitation practices. Our work aimed to investigate the features of SR in athletes and non-athletes depending on BC. The subjects included 10 athletes and 10 non-athletes of both sexes aged 18-30 years. Quantitative indicators of simple visual-motor reaction (SVMR), complex choice reactions (CChR), and reaction to a moving object (RMO) were measured using computer testing conducted with the “Diagnost-1” device, and BC was assessed via bioimped- ance analysis. No differences were observed between athletes and non-athletes in anthropometric indicators, BC, basal meta- bolic rate, SVMR, CChR, and RMO accuracy. Athletes had a greater deviation in anticipation reactions during the RMO test, indicating a predominance of arousal reactions in them. They also had significantly more correlations between SR indicators and anthropometric indicators and BC. In athletes, the spread of latent periods in SVMR was positively correlated with height, weight, body mass index, and basal metabolism, while the central information processing time in the CChR for two of the three signals was negatively correlated. For both groups, the relationship between BC and SR is ambiguous. For athletes' SVMR, lower fat mass is favorable, while for RMO accuracy, higher fat content and mass are favorable. For non-athletes, a lower lean tissue mass favors SVMR, and a higher fat mass benefits CChR.