Myositis ossificans circumscripta is a benign non neoplastic ossifying tumor presenting with bone like osteoid tissue extraskelletaly amidst the muscle planes. This condition when not associated with trauma is very trivial and considering the way it mimics certain characteristics, it may be misunderstood as a malignant neoplasm, abscess or antibioma. The aetiology of this atraumatic condition is still indistinct and remains a question unsolved. We would like to report such a case with distinctly unusual presentation that occurred in our institute. Thereby help in understanding the characteristics of the tumor and associated problems in the diagnoses and treatment.We report a case of 18 year old male presenting with acute onset severe pain in right gluteal region and associated swelling with no history of trauma. All possible investigations including haematological work up, Radiographs, Ultrasonography, aspiration and Magnetic resonance imaging proved to be inconclusive. Open excision and histopathology revealed the condition as myositis ossificans.Our report is aimed towards understanding the difficulty in diagnosing atraumatic myositis ossificans circumscripta and aid in understanding the possible aetiology of unusual presentation without history of trauma.