A seat height adjusting apparatus for a vehicle includes an air spring configured to raise or lower a seat of the vehicle, a control valve connected to the air spring and configured to selectively supply air to the air spring, a push rod configured to selectively press an air injection pin or an air discharge pin of the control valve, an arm rod fastened to the push rod and configured to rotate the push rod, a height adjusting cable fastened to one side of the arm rod and configured to rotate the arm rod, and a height adjusting lever configured to move the height adjusting cable in one direction.