Judo athletes are highly susceptible to chronic muscle damage and oxidative injury. The purpose of this study was to investigate the effect of 8 weeks judo training program on oxidative stress biomarkers and creatine kinase (CK) in male judo athletes. Twenty-four elite male judo athletes were randomly divided into control (C; n=12) and experimental groups (E; n=12). The experimental group (E) performed judo training 6 days/week for 8 weeks. The control group (C) did not participate in any exercise training program during the study. Blood samples were collected 24 h before the beginning of the training protocol, 24 h post-exercise in week 8 and after one week of recovery, to determine hemoglobin (Hb), hematocrit (HCT), blood viscosity, plasma malondialdehyde (MDA), serum protein carbonyls (PC), plasma fibrinogen and serum CK. Eight weeks of judo training increased maximal oxygen consumption (Vo(2) (max)), decreased body mass and fat% in E group. In E group, the levels of MDA, fibrinogen, PC and CK increased at post exercise (P<0.05); and returned to the baseline values after one week of recovery (P>0.05). No significant changes observed in hemoglobin concentration, hematocrit and blood viscosity at post-exercise in both the groups (P>0.05). Increases in oxidative stress biomarkers and CK following judo exercise training may be due to long duration or intensity of judo training and/or not enough recovery. In conclusion, an 8 -wk usual pre-competition training program resulted in increased oxidative stress biomarkers and muscle damage indices in elite judo athletes. Thus, in planning judo training programs sufficient recovery time should be given to prevent excessive oxidative stress and related muscle damage.