Background: Gastrointestinal stromal tumors are rare mesenchymal tumors; and it may be presented by a variety of manifestations.. Case Presentation: A 56-year-old Egyptian male patient presented with a massive gastrointestinal bleeding with hemodynamic instability, with history of previous two mild attacks. After initial resuscitation, endoscopic, pathological and immunohistochemical examination; diagnosis of gastrointestinal stromal tumor was confirmed. The patient's tumor is of low risk and complete surgical excision with safety margins was performed. Another 60-year-old Egyptian female diabetic patient presented for preoperative assessment for cataract operation. On examination large abdominal mass was discovered. After initial diagnostic work up surgical resection was done. Pathological and immunohistochemical examination confirmed the diagnosis of gastrointestinal stromal tumor. Conclusion: Gastrointestinal stromal tumors, should not be overlooked while investigating cases of massive upper gastrointestinal bleeding and cases of large abdominal masses especially in elderly patients