biometric information value acquiring unit for acquiring biometric information value is a value indicating the biometric information of a driver of the vehicle (2), a vehicle speed detecting section for detecting a speed of the vehicle (4), the biological information value acquiring unit (2) is based on the vehicle speed detected by the acquired biometric information value and the vehicle speed detecting section (4), the biological information value reaches a peak value increases than before the deceleration start of the vehicle after the start of deceleration of the vehicle is reduced stable value convergence change degree detecting unit that detects a stable value convergence change degree is a degree of change until a stable value set in advance after the stop of the vehicle (20), stable value convergence change degree detecting section (20) detects depending on the stable value convergence degree of change, and a degree of fatigue estimation unit for estimating the degree of fatigue of the driver (22).車両の運転者の生体情報を示す値である生体情報値を取得する生体情報値取得部(2)と、車両の速度を検出する車速検出部(4)と、生体情報値取得部(2)が取得した生体情報値及び車速検出部(4)が検出した車速に基づき、車両の減速開始後に車両の減速開始前よりも増加してピーク値となった生体情報値が減少して車両の停車後に予め設定した安定値となるまでの変化度合いである安定値収束変化度を検出する安定値収束変化度検出部(20)と、安定値収束変化度検出部(20)が検出した安定値収束変化度に応じて、運転者の疲労度を推定する疲労度推定部(22)を備える。
