Oxidative stress in central and peripheral systems is involved in many diseases, including cancer, cardiovascular diseases, neurodegenerative diseases and several psychiatric disorders. In the present study, the brain and peripheral oxidative status of non-anxious and anxious mice was evaluated using 2',7'-dichlorofluorescin diacetate (DCFH-DA), a sensor of reactive oxygen species (ROS). Here we report that anxiety levels are linked to the oxidative status in both neuronal and glial cells in the cerebellum and hippocampus, in neurons of the cerebral cortex and in peripheral leucocytes (monocytes, granulocytes and lymphocytes), revealing the presence of oxidative stress in the central and peripheral systems of anxious mice. These findings suggest the redox system in anxious mice may play a role in neuroinflammation and neurodegeneration, predisposing them to recurrent infections and chronic inflammation.