Curettage without bone graft was performed in fifteen patients with benign bone tumors and tumor-like lesions. We studied the bone formation after curettage by plain radiography and computed tomography for six or more months. Average period before full-weight-bearing in thirteen patients of the lower extremities was three and a half months. We found no pathological fractures after curettage in any of the patients. Increases in radiodensity and reconstruction of the bone were observed in serial plain radiographs within three months. Computed tomography revealed that the center of the lesions persisted without bone formation, although thickening of cortex bone was predominant. From the data obtained here, it appears that bone grafts may not be necessary in patients, especially in younger ones, with benign bone tumors and tumor-like lesions.