The objective of this study was to evaluate clinical, polysomnography and the multiple sleep latency test (MSLT) features in young narcoleptics. We evaluated 14 patients with mean age of 13.6 years old (ranging from 6 to 18 years) ; 11 were males and 3 females. Daytime sleepiness was the main complaint in all cases and started at the ages of 6 to 17 years. Cataplexy was described in 10 cases and it was considered mild to moderate in all but one case. Sleep paralysis was present in 6 cases and hypnagogic hallucinations in 7 cases. The main polysomnography characteristics were the short sleep latency in 9 cases and the sudden onset of REM periods in 7 cases. The MSLT showed short or borderline sleep latencies in 13 cases, with a mean of 4.9 min; 2 or more REM periods were present in 13 cases. Clinical, polysomnographic and MSLT characteristics in the age bracket focused were remarkably similar to those of adult narcoleptics suggesting the stability of these psysiopa-thological markers.