To provide an air bag device ensuring comfortable interior environment for occupants by preventing noise generated between the air bag device and a steering wheel, when driving a vehicle.

This air bag device is provided with a retainer 30 for retaining an inflator 50, a bag 10 disposed on the retainer 30 covering the inflator 50, a module cover 20 for covering the bag 10, and a horn mechanism 60 disposed at the module cover 20. The horn mechanism 60 comprises a horn plate 61 and a contact plate 62 connected to the horn plate 61. The contact plate 62 has an abutting part 62d formed to abut on a member constituting a spoke part 81 of a steering wheel 80, when connecting the spoke part 81, and a rugged form face is formed at the abutting face of the abutting part 62d abutting on the member constituting the spoke part 81.