The utility model discloses an adjustable burring chamfer sword, including conical blade holder and the handle of a knife of setting on this blade holder, its characteristics are: still include burring cutter assembly, burring cutter assembly includes first blade, second blade, first connection piece and second connection piece, first blade and second blade utilize link bolt movable mounting in V type sword groove, its other end respectively with install first connection piece and the one end activity hinge joint of second connection piece in activity groove an and activity groove b, the other end of first connection piece and second connection piece is through the articulated adjusting bolt activity hinge joint of setting in the adjustment tank. The utility model has the advantages of simple structure, burring cutter assembly can adjust the corner dimension between first blade and the second blade through adjusting articulated adjusting bolt to be suitable for the not burring operation of the round hole of equidimension, also can guarantee required chamfer angle through the contained angle of adjusting between first blade and the second blade simultaneously.