A seatbelt apparatus is provided to apply a proper restrictive feeling on passengers, corresponding to traveling condition of a vehicle. In the seatbelt apparatus, on receipt of detection signals from a fore-and-aft acceleration sensor 97 and a left-and-right acceleration sensor 99, a controller 101 controls respective tensions of seatbelts for driver seat and assistant driver's seat individually. Owing to the controller 101, it is established at a vehicle's braking to make a seatbelt tension of the assistant driver's seat larger than that of the driver seat. When the vehicle is turning, it is carried out to make a seatbelt tension of the driver seat larger than that of the assistant driver's seat.