An occupant protection device configured as an integral bag body including an airbag, the airbag including: a frame duct that includes an upper duct inflated and deployed at a seat upper side of the head of an occupant with a seat front end of the upper duct reaching a seat front side of the head of the occupant in an inflated and deployed state; a front inflating portion that receives gas supplied from a portion of the frame duct that has reached in front of the head, and is that inflated and deployed at the seat front side of the head of the occupant; and a pair of lateral inflating portions that receive gas supplied from the frame duct or the front inflating portion, or both, and that are inflated and deployed at both seat width direction sides of the head of the occupant.