An embodiment roof-mounted type airbag includes a housing to be mounted to a roof part, a center cushion foldable inside the housing and able to be vertically unfolded between facing seats of a vehicle, wherein the center cushion is pillar-shaped, a side cushion foldable inside the housing and able to be unfolded partially along a circumference of the center cushion, and an inflator connected to the center cushion or the side cushion.