With increase of endoscopy, physical trauma including endoscopic procedure can develop gastric submucosal hematoma. Symptoms are usually abdominal pain, vomiting, fever and bloody stool due to upper GI tract obstruction and complications like intestinal obstruction or peritonitis. Diagnosis is usually made by CT, trans-esophageal sonogram and patients with no intestinal obstruction or peritonitis complications and good general condition usually recover with only conservative treatment. Authors have experienced submucosal hematoma developed after submucosal epinephrine injection with intent to uplift distal lesion in gastric polypectomy and improved with conservative treatment.