Passenger protecting device

A passenger protecting device comprising:

• an airbag device including an airbag that is structured as an integral bag body surrounding a head portion of a passenger and that, from a state of being accommodated in a headrest of a vehicle seat, receives a supply of gas from an inflator and is inflated and expanded, by a front expanding portion that includes a front inflating portion to be inflated and expanded at a seat front side of the head portion and at least one of a chest portion and shoulder portions of the passenger, and a pair of left and right lateral expanding portions that include lateral inflating portions that are connected to the front expanding portion and are inflated and expanded at sides of the head portion of the passenger;
• and
• a position changing device that, by operating, changes an inflated and expanded position of the airbag in a seat transverse direction, in accordance with a direction of collision of a collision body with respect to the vehicle seat.