Fatigue of crew member occurs as a result of sleep loss or extended wakefulness, change of circadian rhythm, workload. Fatigue impairs crew member's alertness, it therefore has implications for safety related duties. It is required to monitor and regularly evaluate the fatigue management system to mitigate fatigue related risks. To do this, it is necessary to observe the sleep state directly affecting the crew member’s fatigue. Since the incident of ‘fell asleep’ during flight in 2008, there are increased interest of obstructive sleep apnea which is the reduced sleep quality, and polysomnography which is the standard method to confirm the diagnosis of obstructive sleep apnea. The purpose of this article is to review the efficacy of the polysomnography in terms of the FRMS.