Objectives Rate of gastroesophageal reflux disease accompanied by irritable bowel syndrome is on the increase. This case study reports significant improvement of patients with gastroesophageal reflux disease and irritable bowel syndrome who had suffered from chest pain, globus pharyngis and diarrhea after taking Sasang constitutional treatment. Methods This patient was diagnosed as Large Yin type Esophagus Cold pattern(Taeeumin Wiwanhanjeung). Herb medicine(Jowiseungcheong-tang) was taken by the patient, three or two times per day during treatment periods. We assessed the changes of the main symptoms such as chest pain, globus pharyngis, defecation discomfort, insomnia et al. using visual analogue scale(VAS). Results The symptoms of chest pain, globus pharyngis, defecation discomfort, insomnia decreased from VAS 7~8 to VAS 0~1 for about three months. Conclusions This case shows that Sasang constitutional medicine treatment can be effective treatment method for gastroesophageal reflux disease accompanied by irritable bowel syndrome.