Osteosarcoma is a common primary malignant bone tumor producing osteoid or bone. It occurs very infrequently in the jaws and comprises of 4% of the tumour number as compared to the osteosarcoma of the long bones. Os- teosarcoma of the maxilla is even rarer presenting with common clinical features of pain and swelling. This pre- sented case is a rare case of osteosarcoma of maxilla in a 21-year-old female patient. Diagnosis and pre-operative assessment was performed using a combination of intraoral periapical radiograph, occlusal radiograph, paranasal view and computed tomography (CT). CT revealed destruction of the walls of maxillary sinus and sunray type of ossification in the soft tissues. Conformation was done with histology report followed by surgical removal of the tumor with safety margins. Dental professionals may be the first to detect jaw osteosarcomas in their initial stages. Regardless of the favourable biological behaviour, the patients of jaw osteosarcoma usually exhibit advanced tumor as it often goes unnoticed by the dental professional thus stressing on the need for early diagnosis of the lesion. The aim of this case report is to draw attention to the possibility of diagnosing this tumor based on clinical and radio- graphical characteristics before confirmation by histology.