Under physiological conditions, there is a balance between the production and detoxification of reactive oxygen species (ROS). In the course of several diseases, an overproduction of ROS and their increased reaction with biological macromolecules, lead to disruption of this balance and to enhanced oxidative stress. Alterations in growth hormone (GH)/insulin-like growth factor I (IGF-I) pathway (e.g., in condition of GH overproduction or deficiency) are tightly linked with enhanced oxidative stress. The results of experimental and clinical studies, in which effects of GH and IGF-I on oxidative processes were revealed, are presented in the survey.