Pulmonary hypertension (PHT) is a common complication of sickle cell disease (SCD). Subjects and methods: This is a prospective study that included eighty SCD patients in a steady state. They were subjected to full history, clinical and laboratory examination in addition to Doppler echocardiography and six minute walk test. Result: The mean age of the patients was 12.7 ± 5.5 years. The prevalence of pulmonary hypertension was 28.75%. Prevalence of microalbuminuria was 27.5%. Risk factors associated with PHT was increasing age, longer duration of the disease, frequent vasoocclusive crisis, high platelets count, high reticulocytic count, high serum ferritin, high systolic blood pressure, decreased distance walked and oxygen desaturations during 6 minute walk test. There was weak association between pulmonary hypertension and renal dysfunction. Echocardiography results showed that patients with high pulmonary artery pressure had right ventricular and pulmonary artery dilatation as well as left ventricular dilatation in both diastolic and systolic diameters and volumes than patients without PHT while ejection fraction and fraction shortening of the left ventricle were lower in patients with PHT. There was significant positive correlation between right ventricular diameter and pulmonary artery diameter with tricuspid regurgitant jet velocity. Conclusions: Screening by transthoracic echocardiography must be incorporated into the routine annual evaluation for children with sickle cell disease. Six-minute-walk test can be used as noninvasive index of pulmonary hypertension and cardiopulmonary function in patients with SCD.