A seat belt device includes a belt reel around which webbing is wound, a winding spring that rotationally biases the belt reel in a winding direction, a motor that is configured to transmit a driving force to the belt reel, a clutch that is interposed between the motor and the belt reel, and which performs connection/disconnection of the motor and the belt reel, a webbing speed detection unit that detects the winding speed of the webbing, a fastened/released state detection unit that detects a fastened state and a released state of the webbing, a basic winding control unit that drives the motor in the winding direction in a rotating manner and puts the clutch into a connected state, and a speed increase correction unit that increases the speed of the motor with respect to the speed of the motor obtained by the control of the basic winding control unit.