The present disclosure relates to a height adjustment apparatus of a vehicle seat, whereby during a height adjustment of a seat cushion, a desired tilting angle of the seat cushion is obtained and heights of a front part and a rear part of the seat cushion are individually adjusted. Due to the height adjustment apparatus, the comfort of a seated occupant is improved by adjusting the angles of the seat cushion in response to various postures of the occupant. In addition, a link connection is structurally secured and thus its durability is also improved.