Three cases of chondromyxoid fibroma arising in the skull base are reported. The tumors arose in females 34, 65, and 66 (median 55) years of age. Two women presented with headaches, and one with nasal obstruction. Radiographic studies revealed that all three lesions were expansile soft tissue masses centered in the clivus, at least 4 cm in greatest diameter. One lesion involved primarily the clivus, the others extended from the clivus into the sphenoid and ethmoid sinuses. Two of the three cases were initially misdiagnosed as chordoma or chondrosarcoma. The initial treatment was curettage of gross disease in all three cases. One patient also received radiation therapy. One patient had local progression of disease, which was treated with surgery and radiation therapy. All patients are clinically free of disease 11 to 26 months following the most recent treatment. Chondromyxoid fibroma can and should be distinguished from chondrosarcoma and chordoma, two tumors which more commonly arise in the skull base and which have the potential to metastasize.