The invention discloses an automatic bean vermicelli folding and binding machine and a bending method. The binding machine comprises a rack, a folding mechanism, a clamping shift mechanism and a binding mechanism, the folding mechanism is arranged at the front end of the binding mechanism, and the clamping shift mechanism is arranged above the binding mechanism. The binding method includes that the bean vermicelli is placed between a block pressure bar and a bending push trough; the bean vermicelli is bent in the shape of 'U'; the bean vermicelli is bent to the right side; the bean vermicelli is bent to the left side; a right-bending plate is reset; the bean vermicelli is clamped through the clamping shift mechanism; a left-bending plate is reset, the block pressure bar is allowed to descend, small to-be-bound bundles of the bean vermicelli are shifted out through the clamping shift mechanism to be bound, the block pressure bar is reset, and the bending mechanism is reset as well. By the arrangement, automatic folding, shifting and binding of the bean vermicelli can be realized, folding and binding efficiency is high, overall dimensions of the bean vermicelli are identical, elastic degrees of the bean vermicelli with less burr is appropriate, binding ropes are tied on lateral sides of the small bundles of the bean vermicelli, aesthetic effect of the bean vermicelli is unaffected when the small bundles of the bean vermicelli are put into transparent bags, workers are avoided touching the bean vermicelli during the working process, and further safety and sanitation in food is realized.