ABSTRACT BACKGROUND: Narcolepsy is a chronic disabling central neurological disorder of daytime hypersomnia.  It is categorized into two subtypes-type 1 (N1) and type 2 (N2).  Symptoms of N1 commonly include excessive daytime sleepiness (EDS), cataplexy, sleep paralysis, hypnogogic/hypnopompic hallucinations, and disturbed nighttime sleep.  Ethnic differences have been observed, but they have not been reported in an Ethiopian patient to date.CASE DETAIL: We report a 39-year-old Ethiopian patient with type 1 narcolepsy whose diagnosis was delayed for three decades despite severe symptoms.  Her quality of life was significantly impaired and included EDS, sleep fragmentation, and depression.  The mean sleep latency (MSL) for five naps was 1.3 minutes. Sleep-onset rapid eye movement (REM) periods (SOREMPs) were present in all five nap periods.  HLA-typing and a CSF hypocretin level testing were not performed. Modafinil 300mg was prescribed, which improved her quality of life.CONCLUSION: In developing countries where diagnostic studies are not available, practitioners should pay special attention to a detailed history and look for classic symptoms of narcolepsy to establish an early diagnosis and improve quality of life.KEYWORDS: Narcolepsy, polysomnogram, Ethiopia, sleep disorders