Pneumonia due to Pneumocystis carinii (PC) is characterized, in most cases, by the existence of infiltrates of interstitium or bilateral interstitium-alveolar type on the thorax radiography. However atypical radiological findings associated with this type of opportunistic infection are being described more and more frequently. We present two patients with Acquire Immune Deficiency Syndrome (AIDS) and pulmonary infection due to PC, with very unusual radiological findings. First patient showed multiple pulmonary cavitated nodules; the other a cavitated infiltrate in superior right lobule. Clinicians dealing with AIDS patients must be familiar with this unusual radiologic findings associated with PC in order to avoid diagnostic mistakes.