Introduction The comorbidity of epilepsy and narcolepsy is rare, highlighting a diagnostic and therapeutic difficulty. Observation: We report the case of a 9-year-old girl, with a family history of epilepsy, who presented daily episodes of sudden interruption of current activities and a blank gaze lasting a few seconds, with the notion of daytime sleepiness. The electroencephalogram showed the presence of bilateral and synchronous wave spike discharges of 3 to 5 cycles/second. Brain magnetic resonance imaging was normal. A diagnosis of absence type epilepsy was made, neglecting the drowsiness and the child was treated with valproic acid. However, due to the worsening daytime sleepiness and rapid weight gain, treatment was discontinued. The resumption of the disease history found the notion of faintness leading to falls, with the notion of daytime drowsiness and invincible unexpected sleepiness noted since the age of 4 years old. The polysomnographic recording showed a sleep onset latency of 4 minutes beginning with the R phase with a total sleep time of 7 hours, and an awake time of 1 hour 43 minutes, further confirming the diagnosis of narcolepsy. Critical manifestations have been rare since the initiation of lamotrigine associated with modafinil as treatment.