Chondrosarcoma is a very destructive malignant tumor of cartilage, bone and mesenchymal origin. Localization in the head and neck is rare and the sino-nasal site is even rarer. We report a case of chondrosarcoma of the nasal cavities and sinuses. The aim of our work is to show the importance of clinical, endoscopy and imaging in the diagnostic presumption, to discuss the choice of surgical technique and postoperative monitoring. We will highlight the difficulties that this tumor poses for the pathologist to differentiate between chondroma and chondrosarcoma.