DRIVER STATE DETERMINATION APPARATUS

[Task] To provide a driver state determination apparatus capable of distinguishing a driver's distracted state from another abnormal state such as a disease and promptly and accurately determining the driver's distracted state.[Solution] A driver state determination apparatus 100 includes a controller 10 configured to determine a driver's state on the basis of travel environment information of a vehicle and the driver's sightline. The controller 10 acquires a driving load score on the basis of the travel environment information, acquires a distracted state occurrence score, which represents a degree of likelihood that the driver is brought into the distracted state, on the basis of the driving load score and an elapsed time with the driving load score, acquires a search behavior score, which represents a degree of normality of search behavior by the driver's visual perception, on the basis of the travel environment information and the driver's sightline when the distracted state occurrence score is equal to or higher than a specified value, acquires a distracted state level of the driver on the basis of the search behavior score and an elapsed time with the search behavior score, and determines that the driver is in the distracted state when the distracted state level is equal to or higher than a threshold and the search behavior score is increased in response to an increase in the driving load score.