Fifty-two femoral shaft fractures in children, treated conservatively, were studied clinically and radiographically to access the overgrowth and it is related factors. Among them, we reviewed fourteen children(16 cases), who had angular deformities over 10 after union for the spontaneous correction of the angular deformity. They had an average follow-up of 40.5 months and 32.4 months. The results were as follows : 1. The average of the overgrowth was 9.9mm. 2. The overgrowth was influenced by the age, but was not promoted by other factors. 3. The average overgrowth of the age group between 4 and 9 was 10.8 ± 2.7mm. 4. The average correction was 78% of the initial angular deformity, 77% had occurred at the physes and 23% at the fracture site. 5. There was no close relation between the remodelling rate and degrees of initial deformity.