Background: Bardet-Biedl syndrome (BBS) is an autosomal recessive condition characterized by renal dysfunction, rod-cone dystrophy, postaxial polydactyly, obesity, mental retardation and hypogonadism as a major criteria. Secondary features of BBS include speech delay, strabismus, cataracts, brachydactyly, syndactyly, nephrogenic diabetes insipidus, ataxia/poor coordination, congenital heart disease, left ventricular hypertrophy, situs inversus, anosmia, and hepatic fibrosis. The clinical diagnosis of BBS is based on the presence of at least four primary features or three primary and two secondary features. Bardet–Biedl syndrome (BBS) is a significant genetic cause of chronic and end-stage renal failure in children. Objectives: To study the spectrum of renal and retinal manifestations in patients with Bardet-Biedl syndrome for better clinical phenotyping of the disease in children. Methods: Descriptive cohort study was performed on infants and children with Bardet-Biedl syndrome in Cairo University Center of Pediatric Nephrology and Transplantation during the period from October 2012 to April 2013 (six months). Results: This study included 20 patients with BBS. The median age of cases 9 years (range 1 day to 18 years). Renal involvement in the form of juvenile nephronophthisis was present in 40% of the cases, renal dysplasia in 35% and renal dysplasia with cysts in 20% of the cases. While duplex kidney was found in 1 patient (5%). Sixty percent of the cases had reached ESKD. Visual imparment present in 80% of the cases, night blindness in 45%, retintis pigmentosa in 35% and retinal dystrophy in 60% of the cases. Conclusion: Bardet-Biedl syndrome (BBS) is a pleiotropic disorder with involvement of multiple organ systems. Renal malformations frequently occur in patients with BBS, and renal failure can be a major cause of morbidity. Heterogeneous in nature, renal manifestations of BBS encompass a wide range of disorders that include renal dysplasia or cystic tubular disease such as nephronophthisis. The diagnosis of BBS is often made in late childhood when patients present with recently diagnosed renal failure. Rod-cone dystrophy is one of the major criteria of BBS which become manifest with age. Electroretinographic finding may proceed the presence of retinitis pigmentosa by fundus examination.