AIRBAG APPARATUS

[Problem] To provide an airbag apparatus in which the injury value of a passenger can be efficiently suppressed in an emergency. [Resolution Means] A typical configuration of an airbag apparatus according to the present invention includes: an inflator which is installed in a vehicle so as to be capable of supplying gas; an inner bag which is expanded from in front of a seat utilizing the gas; and an outer bag to which the gas is supplied from the inflator or via the inner bag and expanded so as to surround the inner bag . The outer bag includes an opening which exposes the inner bag towards the seat , wherein the inner bag has a more elongated shape in the anteroposterior direction of the vehicle than in the width direction of the vehicle, and the inner bag further includes a restraining part which is exposed on the recessed surface from the opening to the seat side.