The fully auto pre stretch rewinder mainly includes a frame, an unwinding mechanism, a winding mechanism and a pre-stretching device. The rack includes a left wall panel and a right wall panel arranged oppositely. The winding mechanism includes a main drum and a winding chuck arranged above the main drum. An edge folding device is also arranged between the main drum and the pre-stretching device, and the two ends of the edge folding device are installed on the left and right wall panels. There is also a swing device above the main drum. The winding chuck is installed on the swing device. The swing device includes a swing shaft, a limit device arranged at both ends of the swing shaft, and a motor set at one end of the swing shaft. The swing arm is installed on the swing rotating shaft, the two ends of the swing rotating shaft are respectively installed on the left and right wall plates via a limiting device, and the motor is connected with the limiting device at one end of the swing rotating shaft via an elliptical wheel. The whole machine not only improves the rewinding quality of stretch film, but also guarantees the use effect of stretch film.