Massive bilateral adrenal hemorrhages are a rare complication of anticoagulant therapy. Among over 34,000 autopsies of adults we found six patients with such hemorrhages. Two were women and four men with a mean age of 81 years. They had been hospitalized and anticoagulated for various reasons. The hemorrhage occurred within ten days of anticoagulation, was always bilateral and massive and destroyed the adrenal cortex, thus leading to acute adreno-cortical insufficiency. The diagnosis in all patients was made only at autopsy. Main symptoms are abdominal pain, progressive hypotension, electrolyte disorders and disturbances of consciousness. In patient on anticoagulant therapy, these symptoms justify the suspicion of adrenal hemorrhage and the institution of lifesaving substitution therapy. Pathogenetically these hemorrhages are attributed to the combined effects of stress-induced adrenocortical tissue damage and increased bleeding tendency. The findings in our patients are compared with those of 83 patients from the literature.