The authors have analyzed clinical and radiological materials of sixty patients of lateral condylar fracture of the humerus who have been treated with open reduction and internal fixation and followed up for more than one year since September, 1983. The following results were obtained; l. Age at diagnosis was 5. 9 years in average ranging from four years two months to eleven years three months. Forty-six out of sixty children (76.7% ) were male to reveal definite male preponderance. 2. As for Milch type classification, nine cases (15%) were of type I and fifty one cases (85%) were of type II 3. According to Jakob's staging of displacement, stage I was for seven cases (12%), stage II for thirty five cases (18%) and stage III for eighteen cases (30%). 4. Surgical indications were as follows; Jakob's stage II, III and minimally displaced stage I fractures. 5. The average period of postoperative cast immobilization was 3. 8 weeks. Active and gentle passive motion exercises were instituted thereafter. 6. Limited range of motion of elbow joint was shown in three cases (5%) and overgrowth of the lateral condyle of the humerus was observed by X-ray in ten cases (17%). But non-union was not experienced in any one case. 7. The results of the treatment classified according to Hardacres assessment, were excellent in forty seven cases (78.3%), good in thirteen cases (21. 7%), respectively and no poor case. In conclusion, the focus of the treatment is anatomical reduction without gap and open reduction and internal fixation is considered as the treatment of choice for the minimally dislaced lateral condylar fractures of the humerus in children.