Cerebral aspergillosis carries a high mortality in immunocompromised patients. However, favorable outcome can be achieved by the prolonged use of antifungal agents and the maintenance of adequate drug levels. The authors report a 2-year-old girl who developed an aspergillus brain abscess during treatment for acute lymphoblastic leukemia. Predisposing factors for the fungal infection and details of the antifungal therapy are described. Prolonged treatment with AmBisome and 5-flucytosine successfully eradicated the lesion, but the girl's antileukemic therapy was compromised due to the infection. She developed a central nervous system and bone marrow relapse 9 and 15 months, respectively, after the initial presentation. The report emphasizes the need for further consideration of effective, long-term antifungal prophylaxis and a careful balance between aggressive treatment for severe infection and antileukemic therapy.