The deployment direction regulating structure of the side air bag

Improve the crew of initial restraint performance by the side air bag. In the deployment direction regulating structure of the side airbag (10), an air bag module (38) is disposed in the vehicle width direction outer side of the door-side side frame portion (16A). When the air bag module (38) side airbag provided in is inflated and deployed, the suture portion which is provided between the front skin (22) and the front side skin (24) of the seat skin (20) (30) but, to break in response to the inflation pressure of the side air bag. Thus, an opening for the side air bag is inflated and deployed toward the outside of the seat back (14) is formed. Here, the sewing portion (30) is provided inside the seat width direction than the air bag module (38). Therefore, the side airbag to the inflated and deployed from an opening formed by rupture of the suture portion (30) to the seat back (14) outside, is inflated and deployed toward the front side of the vehicle and vehicle width direction inside (the occupant side) .