The invention provides an adjustable potato harvester which comprises a plow. A plurality of steel bars are arranged at the rear end of the plow side by side. A reinforcing plate is arranged on the lower portion of the plow and provided with a connection plate. The connection plate is provided with a locking plate. The locking plate is provided with at least two adjusting elements, the connection plate is provided with an installation plate in a hinged mode, and the installation plate abuts against the adjusting elements. The harvester effectively solves the problems that in the prior art, when potatoes are harvested, the potatoes are damaged easily, and soil on the potatoes can not be separated from the potatoes easily. Besides, the plowing depth can be flexibly adjusted, and accordingly the potato harvester can be applicable to harvesting potatoes in soil with different thicknesses and is wide in application range.