Background/Aims:?There are currently no standardized guidelines for adequate determination of fasting period following gastric ESD. The aim of this study was to determine the appropriate length of fasting period. Materials and Methods:?Enrolled patients were randomized into a short fasting group and a long fasting group. In the short fasting group, patients had been fasting until the next day after ESD. In the long fasting group, patients had been fasting until two days after ESD. A second-look endoscopy was performed immediately prior to starting diet. The primary end point was a measurement of discomfort related ESD after diet such as epigastric pain, heart burn, regurgitation, nausea and vomiting. Secondary end points included bleeding rate after diet, hospital stay, patient satisfaction and hemostasis upon second-look endoscopy. Results:?We analyzed data from 101 of 110 randomized patients. Both groups demonstrated similar baseline characteristics. There were no significant differences in reports of epigastric pain, heartburn, regurgitation, nausea, and vomiting after diet. Both group demonstrated similar hemostasis rates upon second-look endoscopy (26% vs. 31.4%, p＝0.551) and bleeding rate (4% vs. 0%, p＝0.149). The duration of hospital stay was significantly shorter in the short fasting group (4.12 days vs. 5.11 days, p＜0.001), and patient satisfaction was greater (p＝0.003) compared to the long fasting group. Conclusions:?The short fasting period does not cause discomfort related to ESD nor does it influence post ESD bleeding. Moreover, the short fasting protocol results in shorter hospital stays and greater patient satisfaction.