Tehran University of Medical Sciences Journal of Craniomaxillofacial Research 2345-5489 7 4 2021 02 21 232 235 Samira Derakhshan Department of Oral and Maxillofacial Pathology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Sedigheh Rahrotaban Department of Oral and Maxillofacial Pathology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Samaneh Shirani Department of Oral and Maxillofacial Pathology, School of Dentistry, Tehran University of Medical Sciences, Tehran, Iran. Shima Abbasi Department of Oral and Maxillofacial Pathology, School of Dentistry, Shahed University of Medical Sciences, Tehran, Iran. 2020 10 17 2021 01 24 Mesenchymal chondrosarcoma as an aggressive type of chondrosarcoma shows a characteristic biphasic histopathologic pattern. The head and neck region is included a high proportion of extra skeletal sites. Very rare examples of Mesenchymal Chondrosarcoma involving the mandible have been described. Based on fragmented or tiny specimens, the diagnosis of this lesion has been remained a challenge because the specimens may contain only one of the two neoplastic elements. We report a rare case of mesenchymal chondrosarcoma of the mandible in a 19 years old male with delaying in diagnosis due to massive extension of the tumor to the soft tissues. Keywords: Mesenchymal chondrosarcoma; Mandible; Neoplasm. https://jcr.tums.ac.ir/index.php/jcr/article/view/346 https://jcr.tums.ac.ir/index.php/jcr/article/download/346/314