AIRBAG DEVICE AND PASSENGER PROTECTION DEVICE

An airbag device includes an airbag that is supplied with gas during a vehicle collision, and that inflates and deploys from a rear side of a vehicle seat toward a front side via an upper side thereof. In an inflated and deployed state the airbag includes a pair of front-rear chambers extending in a front-rear direction via left and right sides of the head of a passenger, and an airbag body in communication with the pair of front-rear chambers, that is disposed at a front side of the passenger between the pair of front-rear chambers, and that is compression deformed in a state supported by the pair of front-rear chambers during restraint of the passenger. The airbag is configured such that entry of at least the head of the passenger into gaps between the front-rear chambers and the airbag body is suppressed during a latter half of restraining the passenger.