Machine for harvesting roots planted in the ground and aligned in rows, comprising a unit (36) for horizontally cutting the head of the roots, said unit having a means for automatically adjusting the level of its cutting blade depending on the level of this head, and being followed by a harvesting unit (48) that hollows out the earth beneath the roots at a relative height beneath the cutting level, characterized in that it has a means for detecting the height of the top of the root e, and a means for adjusting the relative height of the harvesting unit (48) with respect to the cutting level, depending on this height.