The work aims to design an automatic binding and knotting machine for woven bags based on double-knot, so as to solve the problems of low efficiency and high labor intensity in manual use of ropes to tie woven bags. According to the manual knotting process, the mechanical knotting process was divided into bunching, knotting, lassoing, fastening, cutting, and other steps. The machine squeezed the bag mouth into a bundle through the clamping action of three air claws and two holding claws. After bundled, the bag was transported to the knotting station by the sliding rail. The special knot expanding device was driven by the motor and the cylinder to complete the rotary knotting and expand the rope loop. The horizontal and vertical slides were combined to put the rope loop on the mouth of the bag, and the knot was pulled from both ends of the rope to complete the automatic binding and knotting of woven bag. Finally, the control system was constructed and the prototype was made for knotting test. The working performance of the prototype was tested and the successful knotting rate of the machine was about 92%, and the average knotting time was about 28.1 s/piece. The research and development of the automatic binding and knotting machine of woven bags can effectively reduce manual labor and have promotion value.