Introduction: With regard to importance of psychological substructures in onset of gastro esophageal reflux disease (GERD), this study was done to investigate and compare the activity of brain/behavioral systems in patients with GERD and healthy people. Method: 60 patients (30 female and 30 male) attending to an outpatient gastrointestinal clinic in Tehran, and diagnosed as GERD cases by a gastroenterologist and 60 other healthy subjects (30 female and 30 male) with the same age average and similar entry criteria were selected as comparison groups. Two groups completed Gray Wilson personality questionnaire (GWPQ). The means of variables in both groups were compared by independent T-test. Results: The activity of behavioral inhibition system (BIS) in GERD patients was significantly higher than healthy people while behavioral activation system’s (BAS) activity in healthy people was significantly higher than patients group. No significant difference was observed in fight/flight system’s (FFS) activity of two groups. Conclusion: Fundamental analyzing of neural/behavioral variables in the study of gastrointestinal disorders is necessary.