Abstract: An airbag is quickly inflated and deployed along an inner side wall of a vehicle while suppressing variations of the deployment direction of the airbag inflated and deployed from an upper part of the vehicle. An upper edge side of an airbag (2), which deploys first, is bellows-folded to form a bellows portion (2J), and a lower edge side continuous with the bellows portion (2J) is roll-folded toward the vehicle's exterior side (G) to form a roll-folded portion (2R). The roll-folded portion (2R) is formed to have a larger width than the bellows portion (2J) in the vehicle's width direction and the both sides thereof are folded back upward. The bellows portion (2J) is folded in substantially half and is wrapped by the roll-folded portion (2R) from below and is accommodated therein.

Abstract: Intended is to always provide effective impact reduction by releasing gas at a timing of pushing into airbag. An airbag (10) has a vent hole (18) in one side end portion. One end of a third base fabric (20) is sewn to the airbag (10) through a first sewn portion (23) that closes the vent hole (18), and the other end of the third base fabric 20 is sewn to the other side end portion of the airbag (10) through a second sewn portion (24). The first sewn portion (23) has weaker binding force by sewing than the second sewn portion (24) so that the first sewn portion (23) is separated to open the vent hole (18) when tension force is applied from the third base fabric (20) to the first and second sewn portions (23) and (24).