Height adjustment apparatus of vehicle seat

A height adjustment apparatus of a vehicle seat having a cushion frame, a position of which is adjusted in upward/downward directions on a seat rail, the height adjustment apparatus comprising:

• a height link having a plurality of links, the height link being rotatably coupled to a side frame of the cushion frame and to the seat rail, and allowing the cushion frame to be moved in the upward/downward directions by the plurality of links being unfolded or folded;
• a drive unit provided on the cushion frame, the drive unit including a power transmission part changeable in a length in forward/rearward directions during an operation of the drive unit;
• and
• a drive mechanism connected to the power transmission part and the height link for operating in cooperation with the drive unit and the height link such that as the length of the power transmission part is increased during the operation of the drive unit, the plurality of links constituting the height link unfolds for the cushion frame to lift,
• wherein the height link includes a first link rotatably provided on the seat rail and a second link rotatably provided on the side frame, and wherein the first link is rotatably coupled to the second link.