Sickle cell disease (SCD), the commonest single gene disorder worldwide, is an inherited disease that has different clinical and hematological manifestations in different populations. The objective of this study is to describe the characteristics of the Lebanese SCD population. This was a retrospective study that included information on 387 patients with either sickle cell anemia (SS) or sickle beta-thalassemia (ST). The mean (+/-SD) age was 17.9 years (+/-12.5), and the mean (+/-SD) follow-up was 9.3 +/- 6.9 years. Fifty percent of the patients were males and SS/ST distribution was 3 : 1. The disease was clustered in two geographic areas in North and South Lebanon. Nearly, all patients were Muslims and 56% were the offspring of consanguineous parents. The prevalence of splenomegaly beyond 6 years of age among SS patients was 28.9%. The prevalence rates of stroke, leg ulcers and priapism were 4.1%, 1.4%, and 0.8%, respectively. Comparing the SS and the ST patients, there were no statistically significant differences in the prevalence of all clinical manifestations except for splenomegaly (SS: 28.9%, ST: 54.9%, P-value < 0.001) and splenectomy (SS: 16.1%, ST: 35.7%, P-value < 0.001). In contrast to Northern American populations and similar to some Mediterranean populations, Lebanese SCD patients have a higher prevalence of persistent splenomegaly. The relatively low incidence of thrombotic complications deserves further investigation. The study's limitations include those of any other retrospective study and the fact that not all Lebanese centers caring for inherited hemoglobin disorders were included. However, the results of this first large scale national survey indicate that preventive efforts should target the Northern and Southern regions of Lebanon to decrease the number of new off springs afflicted with this disease similar to what has been successfully achieved with Thalassemia, another hemoglobinopathy that is highly prevalent in the country.