The subject-matter of the present invention is a selection device (3) for pruning machines (2). The device is designed to selecting branches or sprouts for the pruning, which is performed by means of said pruning machine. The selection device (3) comprises at least one fixing portion (31) so as to be able to be fixed to a pruning machine (2) in a removable manner. The selection device comprises, furthermore: at least one actuator device (4), which is designed to exert a force upon said branches and sprouts, thus moving them so as to cause the branches or sprouts selected for the pruning to be arranged in correspondence to cutting elements (22) provided in the pruning machine, hence at least partially preserving the other branches or sprouts from the pruning; a first frame (33), which is designed to at least partially support said at least one actuator device (4); and at least one regulating mechanism (35), which is fixed to said first frame (33), is associated with at least one actuator device (4), and is designed to regulate at least the direction along which a force is exerted by at least one actuator device (4) associated therewith.