Multiple sclerosis is a progressive inflammatory and demyelinating disease of the central nervous system. Although the primary cause of this disease has not been established yet, it is known that destruction of myelin sheaths and loss of neurons and oligodendrocytes can be observed as disease progresses. It has been suggested that a possible link between neuroinflammation and neurodegeneration could be the phenomenon of oxidative stress. Oxidative stress develops when there are too many free radicals produced within the cell, and the natural antioxidative mechanisms are not effective enough to dispose of them. It has been proven to contribute to the pathomechanism of such neurodegenerative disorders as Parkinson’s disease or Alzheimer’s disease. The role of oxidative stress in the pathogenesis of multiple sclerosis has also been recently confirmed, establishing it as a new target in the disease’s management. Even though the efficacy of such antioxidants as polyphenols, vitamins (A, C, E) and alpha-lipoic acid has been confirmed in many preclinical experiments, no significant effect has been shown in clinical trials. However, some clinical trials related to the use of antioxidants in multiple sclerosis treatment are still in progress. One compound with antioxidant potential that has been proven effective and safe in both preclinical and clinical trials is dimethyl fumarate. It was licensed for the treatment of multiple sclerosis in 2013. Even though its mechanism of action has not been fully established, one of its known effects is the induction of antioxidant pathway related to Nrf2 transcription factor and synthesis of antioxidant enzymes, leading to decrease in oxidative stress.