&NA;A retrospective review of 526 patients who underwent neurosurgery for nontraumatic conditions over a 5‐year period revealed 36 (6.8%) patients with endoscopically and or surgically documented postoperative gastrointestinal (GI) complications. Two patients had GI bleeding and perforation, and the remaining patients had bleeding only. Multivariate analysis indicated 5 factors that were of independent significance in predicting the development of postoperative GI complications. These factors included 1) inappropriate secretion of antidiuretic hormone, 2) preoperative coma (Glasgow Coma Score <9), 3) the presence of postoperative complications, 4) age ≥60 years, and 5) pyogenic infection of the central nervous system. Further analysis of the 36 patients with GI complications revealed that they could be divided into three groups with different clinical courses. In Group I (n = 10), all patients died as a result of their neurological conditions; GI complications were just preterminal events and did not require treatment. In Groups II (n = 11) and III (n = 15), GI complications were symptomatic and life‐threatening events, respectively. Eleven patients from Group III died as a direct result of the GI complications. Separate multivariate analyses based on the patients in Groups II and III revealed that preoperative coma was the only significant factor that predicted the occurrence of life‐threatening complications. Patients who are at high risk of developing postoperative GI complications can thus be identified, and intensive prophylaxis may be instituted. (Neurosurgery25:378‐382, 1989)