A seatbelt device for a vehicle includes a belt reel for winding a belt for restraining a target object, a motor for driving the rotation of the reel, and a control unit. The control unit determines whether the target object to be restrained is a child seat or a vehicle occupant on the basis of a winding position of the belt while no electricity is being supplied to the motor and the winding position of the belt when electricity is being supplied to the motor.