Gastroesophageal reflux disease (GERD) is a global health problem in which the prevalence is increasing over periods. This disease is a significant cause of disorders in the upper gastrointestinal tract with very complex pathogenesis. Oxidative stress (OS) due to gastric acid reflux plays a role in the inflammatory response of the esophageal epithelium. Several OS markers have been widely studied and are thought to affect the severity degree of the esophageal mucosa. However, there has been no research on total oxidant status (TOS), total antioxidant status (TAS), and OS index (OSI) in the adult with GERD; hence the aim of this review was to determine the association between TOS, serum TAS, and OSI with the GERD degree. A literature review was conducted by searching articles related to the TOS, TAS, OSI, and its correlation with GERD degree on an online database, particularly Pubmed and Google scholar. We conclude that TAS and OSI might influence the severity of GERD; however, further clinical study is needed to prove this theory.