The diagnosis of delayed rupture of the spleen may be difficult to make because of the presumed triviality of the precipitating injury, an unpredictable time lag between the injury and the development of symptoms, and the possibility of atypical signs and symptoms remote from the bleeding spleen. The clinician may confuse the signs and symptoms with those of acute appendicitis or with some other cause. The authors present two case histories to illustrate the diagnostic difficulties caused by delayed rupture of the spleen. Whenever the acute surgical abdomen is present with concomitant anemia, the diagnosis of delayed rupture of the spleen should be considered.