A 50-year-old man developed invasive pulmonary aspergillosis after induction chemotherapy for acute lymphoblastic leukemia. He was treated with 5-fluorocytosine and intravenous amphotericin B (AMPH-B). During antifungal therapy, he developed aspergillus pericarditis and complete atrioventricular (A-V) block. The pericardial effusion was decreased and the A-V block was improved after treatment with intravenous and intrapericardial instillation of AMPH-B. Because the patient's renal function deteriorated, AMPH-B was replaced with itraconazol after the latex agglutination (LA) test for an aspergillus-specific antigen showed a negative result. The patient, however, died from disseminated aspergillosis. Aspergillus DNA was detected in retrospective analysis of the serum which had been negative with the LA test. This case indicates that LA is not sufficient for diagnosis and post therapy evaluation of invasive aspergillosis. PCR or other methods should be used concomitantly with LA. Intrapericardial instillation of AMPH-B might be effective for patients with aspergillus pericarditis in whom surgical treatment is not indicated.