Provided is a seatbelt device which prevents an occupant from hitting his face against an airbag deploying at the time of a vehicle collision. In order to take up any seatbelt slack before a collision and prevent the occupant from being displaced forward, the seatbelt device comprises a first tension modifier for winding the seatbelt and taking up the seatbelt slack when a collision is predicted, and a second tension modifier for further enhancing the tension of the seatbelt and securing the occupant to the seat at the time of such collision, thereby ensuring that the occupant does not exist in the airbag deployment zone when the airbag is activated.