Abstract: A loadport for a semiconductor fabrication machine that is equipped with an automatic height adjustment means and a method for operating the loadport are described. The loadport consists of a moveable platform for carrying a wafer cassette thereon and supported by at least two support members capable of moving the platform in an up-and-down direction. A distance sensor is mounted on a bottom surface of the platform for measuring a height of the platform. A process controller is used to receive a first signal from the distance sensor, comparing to a pre-stored datum and then sending a second signal to the at least two support members to move the platform until the first signal equals the pre-stored datum.