PROBLEM TO BE SOLVED: To provide a fatigue degree estimation device capable of accurately estimating a fatigue degree of a driver.SOLUTION: A navigation device 700 acquires mode information indicating a travel mode of a vehicle by an acquisition part 701. The navigation device 700 determines a support degree of a drive support system on the basis of the acquired mode information, and estimates a drive fatigue degree of a driver on the basis of a fatigue degree coefficient (F) corresponding to the determined support degree, and drive duration time of the driver, by an estimation part 702. Therefore, the drive fatigue degree according to the level of the drive support can be estimated, thereby the fatigue degree of the driver can be accurately estimated.
