A 32-year-old male was admitted to our hospital complaining of fever and dyspnea on effort. Laboratory data on admission indicated leukocytosis and elevation of C-reactive protein. A chest radiograph showed diffuse reticulonodular shadows in both lower lung fields, and a chest computed tomography showed centrilobular reticulonodular opacity. Bronchoscopic findings revealed a large amount of slightly yellowish secretion in all bronchi. Cells found in the bronchoalveolar lavage fluid (BALF) included 61% neutrophils. Haemophilus influenzae was isolated from cultures of the BALF and sputum. Transtracheal lung biopsy specimens showed focal infiltration of neutrophils in the alveoli, and the pathological findings in the lung were compatible with bronchiolopneumonia. Since the CD4/CD8 ratio was 0.09 and a positive reaction was obtained for anti-human immunodeficiency virus (HIV) antibody, HIV-associated pneumonia due to H. influenzae was diagnosed. Seven days'administration of cefozopran improved the patient's condition. It is interesting that radiological findings are often unusual in HIV-infected patients with H. influenzae pneumonia.