A curtain airbag apparatus (100) is provided with an inflator (106), and a cushion (102) stored, in an elongated storage form, on an inner side of a headliner above a front side window (110), and receives the gas to inflate. The cushion (102) in the storage form has a bent-over portion (142) which is formed by bending over a rear end (136) of the cushion (102) towards a center side thereof from a state in which the cushion (102) is rolled upwards. The state of the cushion (102) when the bending over is performed i.e. the rolled state of the cushion (102), is achieved by rolling the cushion (102) from a state in which a prescribed area at the rear end (136) of the cushion (102) in a deployed state is folded over towards the center side in the vehicle front-rear direction.