Provided are a check valve for an airbag and an airbag device that can improve the reproducibility of the flow path blocking function while reducing the resistance upon inflation and deployment of the airbag and that can be applied to a place where a flow path is divided into a plurality of flow paths. A first embodiment of an airbag device according to the present invention has an airbag that is normally folded and that is inflated and deployed in an emergency, and an inflator that supplies gas to the airbag. The airbag has a plurality of inflation chambers, a duct portion disposed so as to connect the plurality of inflation chambers, and a check valve for an airbag having a tubular portion sewn to the duct portion, and tongue-shaped portions formed at the tip of the tubular portion.