Vitamin D deficiency is known to be common among patients with sickle cell anemia (SCA). Vitamin D levels were measured in 139 children (aged 7.9 to 15.1 years) to study its association with SCA morbidities; severe deficiency <10 ng/mL was present in 64.0% and only 2.2% were sufficient (>30 ng/mL). Vitamin D levels were associated with pulmonary function (forced expiratory volume in 1 second [FEV(1)]), but not associated with either rates of acute pain or acute chest syndrome episodes. Further studies are needed to be able to compare outcomes in those with deficiency to those with sufficiency, as well as to treating patients with SCA with vitamin D to better establish a possible link, if any, between vitamin D and SCA morbidity.