AIR BAG DEVICE

[Object] To provide an airbag apparatus having an inflator in which the waterproofing property of the connection between an initiator and a harness for distributing power is ensured by potting, and leakage at the time of the filling of a potting material is prevented. [0002] [Solution] An airbag apparatus 100 includes a bag portion 110 formed of a base cloth panel in a bag shape and deployed and inflated by being supplied with gas for deployment, and an inflator 200 that generates the gas for deployment supplied to the bag portion. The inflator includes a gas-generating agent, an initiator that causes the gas-generating agent to start gas-generating reaction, a housing 210 that houses the gas-generating agent and the initiator, a harness for distributing power 230 that supplies power to the initiator from the outside through an opening 210a formed in the housing, a cap member 250 disposed so as to face the surface of the housing around the opening, an annular elastic member 260 disposed so as to surround the opening and so as to be sandwiched between the surface of the housing and a surface portion 251 of the cap member facing thereto, and a potting material P filled in a space between the housing and the cap member on the inner side of the elastic member.