Sickle-cell anemia is a hereditary hemoglobin disorder among children. We showed that the low bone mass is prevalent among these children, and it has a negative association with hemoglobin. In spite of using supplementary 200 IU/day vitamin D, 59.6% of children with sickle-cell anemia are vitamin D deficient. We suggest that early diagnosis and treatment of this problem could improve the bone health in them.