The invention provides an electronic shoulder strap restraint device and method.The device comprises an end cover, a shell, a rolling wheel, a shoulder strap, a first bearing, a second bearing, a motor, a control module, a three-way acceleration sensor, a tension sensor and a cable, the shoulder strap is wound around the rolling wheel, and the rolling wheel is supported and limited through the first bearing and the second bearing and connected with the motor; the motor, the control module, the three-way acceleration sensor and the tension sensor are connected through cables; the two ends of the tension sensor are mechanically connected with a passenger and the shoulder strap respectively, and are connected with the control module in the shell through a cable; except for the tension sensor and part of the cable, the other parts are installed in the shell, and the two ends of the shell are sealed through the end covers.