An airbag device includes an airbag main body, a storing section, an airbag lid member, a hinge section and a protective member. The airbag lid member has a lid section and an opening section. The lid section is configured to be opened by a pressing force of the airbag main body. The opening section is formed when the lid section is opened. The hinge section couples an edge portion of the opening section and the lid section. The protective member is configured and arranged to be disposed between the airbag main body and the hinge section when the airbag main body expands, and has a main protective section and a peripheral portion protective section. The peripheral portion protective section is provided on both sides of the main protective section to cover at least a peripheral portion of the lid section which protrudes from both sides of the hinge section.