The present invention relates to an automatic tying machine for automatically tying binding wires in order to fix crops in a farmhouse or tie bundles or bundled products during distribution. More specifically, the present invention relates to an automatic tying machine which can use binding wires of different thicknesses, in which after a binding wire is drawn into a slot of a whirling binding wire guide device, the binding wire does not slip off from the slot during rotation of a slewing gear to prevent malfunctioning of the automatic tying machine for crops, such that it is possible to accurately and quickly tie crops, bundles or bundled products. Due to these features, the automatic tying machine has remarkable effects that can improve the productivity of work of tying crops, bundles or bundled products and improve work convenience.
