: We report an 8-year-old boy diagnosed with both CMT1 and narcolepsy, which were not reported simultaneously presenting in one person. The boy presented with a history of increased suddenly falling frequency and excessive daytime sleepiness for 3 months. CMT1 was diagnosed by electrophysiology and genetic testing. Narcolepsy had not been diagnosed until the frequently falling caused by sudden and transient episodes of legs weakness triggered by emotion was found. Multiple sleep latency test showed multiple sleep onset REM periods with reduced sleep latency. When CMT1 and narcolepsy were coexist in an individual, the latter might be overlooked. Cataplexy caused by narcolepsy might be disregard as distal muscle weakness of CMT1. The daytime sleepiness might also be ignored. Therefore, we recommend that patients with sleep disorders should be queried about the symptoms of narcolepsy.