A seat includes an airbag module fixed to a seat frame, a trim cover including a breaking part which breaks according to an inflation and a deployment of an airbag of the airbag module, a first stay cloth and a second stay cloth which guide the inflating and deploying airbag to the breaking part, a first fixing member which is attached to the backside frame and stretches and supports the first stay cloth, and a second fixing member which stretches and supports the second stay cloth, in which the backside frame is provided with a pair of first attachment holes into which both end portions of the first fixing member are inserted and a pair of second attachment holes into which both end portions of the second fixing member are inserted.