Indoor climbing is a worldwide sport with particular physiological and physical demands. With this study, it was aimed to investigate the effects of indoor climbing on oxidative stress, antioxidant levels and hematologic parameters. All results in the study were analyzed via using non-parametric Wilcoxon test with Statistical package for Social Sciences version 17 for Windows, with p<0.05 as the criterion for significance for all statistical comparisons. Fifteen voluntary male students whose average age is 22,35 ± 2,65 years old, participated in this study. These subjects were climbed 30 ± 1,25 times during eight weeks. Blood samples were collected at rest, 24h before, and 24h after climbing protocols to analyze total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI) and hematologic parameters [Hemoglobin (Hb), hematocrit (Hct), platelet (Plt) and leukocyte (Wbc)]. Resting heart rates were measured at the same time. According to our findings, TOS (1,47 ± 0,06, 1,51 ± 0,02) (P:0.042) significantly increased, TAS (1,56 ± 0,04, 1,52 ± 0,03) (P:0.036) significantly decreased and OSI (0,94 ± 0,02, 0,99 ± 0,05) (P:0.014) significantly increased with climbing. There has been no statistically relation among the hematologic parameters. Data demonstrate that indoor climbing leads to increased plasma oxidative stress in sedentary individuals and can affect the athletes performance negatively.