The invention provides a double-channel cop inserting device for an automatic winder and a cop inserting method. The double-channel cop inserting device comprises a control system, a cop conveying device, a cop end size judgment device, a cop releasing device, an upper hopper, a first lower hopper, a second lower hopper, a first tray channel and a second tray channel. The double-channel cop inserting device is characterized in that the upper hopper is of a t-branch pipe structure, a cop inlet is formed in the upper portion of the upper hopper, and the lower portion of the upper holler is bifurcated into a first cop arrangement pipeline and a second cop arrangement pipeline. A lower end opening of the first cop arrangement pipeline is aligned with an upper end opening of the first lower hopper. A lower end opening of the second cop arrangement pipeline is aligned with an upper end opening of the second lower hopper. A lower end opening of the first lower hopper is aligned with trays to be subjected to cop inserting on the first tray channel below the first lower hopper. A lower end opening of the second lower hopper is aligned with trays to be subjected to cop inserting on the second tray channel below the second lower hopper. A movable baffle is arranged in the upper portion of the upper hopper and is controlled through a control system by means of a drive mechanism to selectively block the upper end opening of the first cop arrangement pipeline or the upper end opening of the second cop arrangement pipeline. The double-channel cop inserting device is simple and compact in structure, low in manufacturing cost, convenient to maintain and high in cop inserting efficiency.