Behcet’s disease (BD), first described by the Turkish dermatologist Hulusi Behcet in 1937, is characterized by triad of symptoms that include oral aphthous lesions, genital ulcerations and iritis with hypopyon. The etiopathogenesis is not yet fully explained, although reactive oxygen species produced (ROS) by the hyperfunction of neutrophils which are significant for the immune response are thought to play a role. Antioxidant defense system protects the body against the harmful effects of reactive oxygen species. Normally, there is a balance between reactive oxygen species and antioxidant defense system but as levels of reactive oxygen species are above the body’s neutralization and elimination ability disrupts the balance. With the imbalance, increased levels of reactive oxygen species disrupt biomolecules such as lipids, proteins, nucleic acids and cause cell, tissue and organ damage. Studies with parameters associated with antioxidant defense system are included in our study. When viewed as whole, most of the studies support that imbalance between oxidants/antioxidants plays a role in etiopathogenesis of Behcet’s disease but it should not be forgotten that there are studies show otherwise. Reactive oxygen species affect patients with active disease more than patients with inactive disease. In conclusion, studies classified in detail with larger group of patients on Behcet’s disease are needed. If patients’ clinical findings and levels of oxidants and antioxidants are interpreted together in the studies, they can be used to monitor the disease and success of the therapy