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Purpose To describe the phenotypic characteristics of seven families with childhood onset retinal dystrophy in Northeastern Tunisia and to determine the linkage with RPE65 gene mutation. Methods Seventy subjects were concerned (18 affected patients and 52 unaffected). Ophthalmic examinations included visual function testing, fundus examination, full field ERG, spectral OCT and fluoroangiography. After patients consent, screening of RPE65 gene was performed by bi‐directional sequencing. Results All affected members had a severe retinal dystrophy with history of low visual acuity since infancy. The age at first ophthalmic examination ranged from 5 to 55 years old. Visual acuity ranged from no light perception to 2/10. Two retinal patterns were identified: the first one presented midperipheral white dot deposits, whereas the second showed midperipheral pigmented clumps without any white deposits. Atrophic and /or pigmentary macular changes were present in most patients. Mutational screening of the RPE65 gene identified an homozygous R91W mutation co‐segregating with the disease in 11 affected individuals. Two siblings were compound heterozygous for this mutation. Conclusion We identified and characterized an endemic form of early onset rod‐cone dystrophy in a consanguineous population from northeastern Tunisia, due to the prevalence of a single single homozygous missense R91W mutation in exon 4 of the RPE65 gene. This could have practical value for genetic screening strategy in young affected tunisian patients. [ABSTRACT FROM AUTHOR]