The invention provides a vehicle height adjusting device which comprises a spring base component and an adjusting shaft, wherein the spring base component is supported on a wheel-side component and provided with a spiral spring with a small-diameter thread part, and the adjusting shaft is spirally combined with the spring base component; the bottom of the spring base component is integrally formed into a bolt body; the adjusting shaft is spirally combined on the bolt body at the bottom of the spring base component, and an outer hexagon is arranged at the lower end of the spring base component; adjusting cushion blocks with corresponding specifications are arranged between the spring base component and the wheel-side component and used for adjusting the vehicle weight; an adjusting sleeve is sleeved outside the adjusting shaft; an outer hexagon is arranged at the lower end of the adjusting shaft; and a flange face which is supported on a step face inside the adjusting sleeve is formed at the lower end of the adjusting shaft. By arranging various specifications of adjusting cushion blocks, the invention improves the adjusting range of the whole vehicle weight; and as main stress points in the structure are not positioned in the thread part any more, the invention increases the mechanism reliability, reduces the thread failure probability, prolongs the service life of the mechanism and accelerates the assembly process.