SIDE AIR BAG FOR VEHICLE

A side airbag (10) for a vehicle including an inflator part (11) that discharges an inflation gas; and a cushion part that covers the inflator part, is deployed by the gas discharged from the inflator part. The cushion part includes a main chamber part (13) deployed between a passenger and a vehicle body, and a protruding chamber part (15) extended from the main chamber part and deployed in front of the passenger.