INTRODUCTION: Cytokines are important regulators of physiological growth through their direct interaction with the growth hormone – insulin-like growth factor-I axis, through that are mediated anabolic effects of exercise (Scheett et al., 1999; Nemet et al., 2002). Moreover, cytokines provide a link between the immune and endocrine systems to modulate adequate responses to different stressors (Elenkov, 2008). While acute changes in systemic pro-/anti-inflammatory cytokines occur with exercise in children (Rosa et al., 2007), effects of exercise on salivary cytokines and their relationship with cortisol in young athletes remain poorly studied. The purpose of present study was to examine effect of a single session of exercise on salivary cytokines and salivary cortisol in young male judoists. METHODS: Nine prepubertal boys aged from 8 to 10 years (Group 1) and eighteen adolescent boys aged from 13 to 16 years (Group 2) practicing judo were involved in the study. Mothers of all participants signed a voluntary informed consent. None of the participants was suffered from acute or chronic diseases of oral covary. Saliva samples were obtained before and after a routine judo session (mixed muscle type of training, 1 h 30 min, motor density of the session is 80%). The concentrations of IL-6, IL-8 and cortisol were determined using ELISA. Values are medians and interquartile intervals (Me; Q1-Q3), compared by non-parametric models. Statistical significance was accepted at P<0.05. RESULTS: It was found that salivary concentrations of IL-6 and IL-8 were higher in adolescents when compared with children before a session of judo (IL-6:  31.2; 17.9-51,9 vs. 17.05; 8.17-23.1 pg/mL, P<0.05; IL-8: 1417,5; 706,0-1899,0 vs. 158,2; 104,6-502,0 pg/mL, P<0.05, respectively). A single session of judo did not affect the salivary IL-6 content in both adolescents and children. In contrast to IL-6, IL-8 levels increased after judo session in both children and adolescents. Thus, the content of IL-8 in saliva in children after exercise raised in 2.5 times and was 390.0; 222.0-494.0 pg/mL (P<0.05). In adolescents, the post loading level of IL-8 in saliva increased in 1.4 times to 1998.0; 1299.0-2234.0 pg/mL, P0.5; adolescents: 15.9; 9.49-24.9 vs. 24.05; 14.4-33.2 ng/mL, P>0.5, respectively). CONCLUSION: Taken together, our results indicate that а single session of judo does not lead to a change in salivary concentration of cortisol in children and adolescents. This is likely due to the adaptation of body to regular training. We also demonstrated that the concentrations of IL-6 and IL-8 in saliva depended on the age of children, and the effects of exercise on these cytokines were different: the level of IL-6 did not change, and the concentration of IL-8 in saliva increased after training. Probably, it is due to the fact that the stress reactivity of salivary cytokines can reflect not only the processes in the immune system and in the hypothalamus-pituitary-adrenal system but also depends on the activity of the sympathetic nervous system.