Provided are a physiological condition estimation device and a vehicle control device capable of preventing an error in the operation of an apparatus, such as a vehicle, and improving the safety of the operation of the apparatus. The physiological condition estimation device includes an eye-open time acquiring unit that acquires the eye-open time of the driver, a variation calculating unit that acquires a variation in the eye-open time acquired by the eye-open time acquiring unit, and a drowsiness predicting unit that determines the physiological condition of the driver on the basis of the variation in the eye-open time acquired by the variation calculating unit. In this way, since the physiological condition is determined on the basis of the variation in the eye-open time, it is possible to detect a slight reduction in the arousal level and estimate a significant reduction in the arousal level to a value that will cause an error in the driving of the vehicle in the future.