Twelve elderly patients without Waterhouse-Friderichsen syndrome or adrenal tumor who had spontaneous adrenal hemorrhage one to 33 days after operation are described. Seven of these patients had operations on the gastrointestinal tract, one on the biliary system, two on the genitourinary system and two on the central nervous system. Important factors relating to adrenal hemorrhage included: intra-abdominal sepsis in 5 patients, cancer in 4, pneumonia in 4, coagulation defects in 2, exogenous steroids in 2, and syphilis in one patient. Spontaneous adrenal hemorrhage should be considered in patients whose condition deteriorates rapidly after operation and in whom no other explanation is plausible. Its detection and appropriate therapy can be lifesaving.