We retrospectively evaluated the neurologic complications in 425 patients who underwent bone marrow transplant (BMT) (310 allogeneic, 115 autologous) for leukemia. Forty-six patients (11%) developed 47 central and three peripheral neurologic complications. The most common complications were cerebral hemorrhage (3.8%), metabolic encephalopathy (3%), and CNS infections (2%). All CNS infections occurred with allogeneic BMT. Eleven of 16 hemorrhages were subdural hematomas (69%), which were more frequent in autologous (8%) than in allogeneic (0.6%) BMT (p < 0.0001), and in patients with acute myelogenous leukemia (AML) (5%) than in the remaining leukemia patients (0.8%) (p = 0.013). Eight of 11 subdural hematomas occurred in AML patients receiving autologous BMT. When we compared patient-, disease-, and transplant-related characteristics of these patients with those without subdural hematoma, only platelet refractoriness correlated with an increased risk of subdural hematoma. The actuarial probability of developing subdural hematoma was 44% in patients with platelet-refractory disease and only 2.5% in the other patients (p < 0.0001). Ten patients with subdural hematoma did not have surgery and eight had significant clinical improvement associated with reduction or resolution of the hematoma, confirmed by CT scan in six patients. The subdural hematoma was the cause of death in only one patient. This study shows that the frequency of the different neurologic complications varies among types of BMT. Patients undergoing autologous BMT for AML with platelet refractoriness have an increased risk of subdural hematoma that may be treated with conservative measures.