The 35 patients who have suffered from myositis ossificans were investigated for 11 years. They wereposttraumatic patients, They trauma was divided into 3 groups; spinal cord injury, direct injury(fracture) andmixed type involving both. We evaluated the age distribution, the frequency of myositis ossificans, predilectionsite, bilaterality and relation between predilection site and bilaterality to the type of trauma. The results areas follows; 1. The age distribution was highest in 4th decades(12 among 35 patients). 2. In regard to distributionof 35 patients, spinal cord injury were most common (15 cases, 43%), the fracture nextly common (14, 40%) and thenmixed type (6,17%). 3. Among 51 cases of myositis ossificans, the frequency was highest in spinal cord injury(25cases, 49%), next was fracture(14, 27%). 4. The correlation between predilection site of myositis ossificans andlevel of spinal cord injury, hip is the most frequent site in thoracic injury. 6. The bilaterality of myositisossificans is 39%(20 among 51 lesions).