Dedifferentiated chondrosarcoma is an uncommon malignant cartilaginous neoplasm of bone characterized by the presence of a malignant spindle cell neoplasm associated with a low- or medium-grade chondrosarcoma. Origin of this tumor in the cartilagenous framework of the larynx is very rare. A 60-year-old male with a 2-year history of hoarseness and dyspnea was examined while presenting in acute airway distress. Direct laryngoscopy revealed a mass of the right side of the larynx. Histopathologic examination revealed a malignant cartilaginous tumor with a malignant spindle cell component. We report a case of dedifferentiated chondrosarcoma arising in the thyroid cartilage. This, to our knowledge, is the eleventh fully documented case of this neoplasm arising in the larynx.