An apparatus for automatically pruning vines grown in a row in a cordon-leading manner has a chassis, a pre-pruning module, a clear-cutting module and a position sensor. The clear-cutting module is positioned behind the pre-pruning module and has cutters thereon. The position sensor is forward of the clear-cutting module so as to locate the cordon and to position the cutter so as to achieve a clear cut from a periphery of the cordon. The clear-cutting module has upper cutters, lower cutters and lateral cutters.