To evaluate the usefulness and clinical significance of scintigraphy using 99mTc-RBC in urgent abdominal bleeding, we performed abdominal bleeding scintigraphy in 20 patients with melena. These patients were admitted to the critical care center. Nine of 20 patients showed positive images with bleeding scintigraphy. Five of 20 patients were referred because of small intestinal bleeding. Four of these 5 patients revealed positive images. Seven of 9 patients who had positive image and four of 11 patients who were negative had open-surgery performed. While angiography was done in 8 patients, only 3 of the 8 patients were proven to have bleeding. These 3 patients also revealed positive images by bleeding scintigraphy. This technique facilitates the screening of bleeding in the ileum, where endoscopic techniques may prove difficult to detect the site of bleeding. We emphasize that abdominal scintigraphy should be performed on patients with G.I. bleeding since this is a more accurate examination than angiography.