Intrapulmonary teratomas are rare; only 30 cases have been reported in the world literature. These tumors are thought to originate from the third pharyngeal pouch. They occur equally in men and women and usually are diagnosed in the second to fourth decade of life. They are more often benign than malignant, although malignant lesions may have a favorable postoperative prognosis and benign lesions may exhibit high morbidity and mortality because of their size and location. These tumors present radiographically as lobulated masses that may contain calcification or peripheral collections of air. They most often occur in the upper lobes. The computed tomographic findings of intrapulmonary teratoma are less well known but have been described in two cases. An additional case is presented with a review of the literature and a tabular summary of the characteristics of this unusual entity. © 1992 Aspen Publishers, Inc.