Background: This study aimed to investigate the effect of the treatment with corticosteroids, and to identify different factor associating to the bone density of the spine and femoral head increases. To this end, the bone mineral densities of the spine and femoral head in children suffering from different types of congenital adrenal hyperplasia were assessed; and their association with some other factors, along with the effects of the treatment was investigated. Method: This retrospective and descriptive cohort study was done in Iran from 2020 until 2021, on 44 patients with mean age of 10 years old. Forty-four patients, including 18 males and 26 females with a mean age of 10 years were enrolled in this study. They were treated with corticosteroids with a physiological dose of 15-20 mg/m2 since infancy. Patients (parents) filled a form providing demographic information and the disease history and responded to questions about taking supplements and any other type of medications, doing exercise, having a history of fractures in patients or other family members. Result: The bone density level was not correlated to the duration and dose of corticosteroid consumption, age, sex, time of diagnosis, 17-hydroxyprogesterone level, calcium, and phosphorus. Other factors such as height, weight, puberty stage, and vitamin D levels had significant roles in determining the bone density level. There was a positive correlation between height and bone density, which means that the taller the patient, the higher the bone density of the spine and femoral head. As patients gain weight, the bone density of the spine and femoral head increases. With increasing vitamin D levels in patients, the femoral head bone density increases and vice versa. Conclusion: Bone densitometry should regularly be done, osteoporosis prophylaxis should be considered using weight-bearing exercises and calcium and vitamin D supplements, and the level of vitamin D should be monitored. The dose of corticosteroids should be adjusted.