Pneumocystis carinii pneumonia(PCP) remains the leading cause of death in patients with AIDS. Although the most common radiographic presentation of PCP is the developme-nt of diffuse, bilateral interstitial or alveolar infiltrates in 48 to 86 per cent of AIDS patients, PCP may also present with either a completely normal or only minimally abnormal chest radiograph in 6 to 23 per cent of patients. We experienced two patients with AIDS presenting high fever and chest pain but normal chest radiograph, who had been proved to have PCP by bronchoalveolar lavage and trans-bronchial lung biopsy.