OCCUPANT DETERMINATION DEVICE

To provide an occupant determination device capable of improving reliability in results of determining an occupant's physique. An occupant determination device includes a tentative-determination processing unit provided in a seat of a vehicle and classifying a physique of an occupant seated on the seat by comparing a determination value set based on sensor values of a plurality of load sensors for detecting loads applied to the seat with predetermined load threshold values, and a determination processing unit determining the physique of the occupant by using tentative determination results by the tentative-determination processing unit, in which, when the number of the tentative determination results classified into a given class becomes equal to or larger than a predetermined threshold value in the tentative determination results of a predetermined number of samples, the determination processing unit determines the physique of the occupant to be the given class.