Tc-99m labeled RBC imaging is becoming increasingly useful in detecting gastrointestinal (GI) bleeding sites. A patient is presented who had massive GI bleeding from an unsuspected gastric leiomyoma in whom a Tc-99m sulfur colloid GI bleed image was negative. The Tc-99m labeled RBC imaging done on the day after sulfur colloid imaging revealed increased gastric activity due to active bleeding from an intragastric leiomyoma. Tc-99m labeled RBC imaging helped in early detection of the bleeding site resulting in its successful treatment. This experience also reinforces the assertion that Tc-99m labeled RBC imaging may be more helpful than Tc-99m sulfur colloid imaging in patients with upper GI or intermittent bleeding.