Duplicated cyst is a rare congenital disease that makes up 4% of all gastrointestinal duplications. It is two times more prevalent in women than in men. The majority of cases are detected by such symptoms as an abdominal mass, nausea, abdominal pain and anemia in infants, but these symptoms are uncommon in adults. Obstruction, hemorrhage and perforation are possible complications and malignancy can develop on rare occasions. Most cases are controlled by surgical resection. We report here on a case of gastric duplication cyst in a 20-year-old woman who presented with severe nausea and vomiting. She was managed by surgical resection after evaluation was done via endoscopic ultrasonography.