A height adjustment mechanism is provided. The height adjustment mechanism includes a lifting arm, a driving mechanism configured to drive and lock the lifting arm, and a control switch configured to control the driving mechanism; the driving mechanism is coupled to the lifting arm, and an angle is formed between the driving mechanism and the lifting arm. A height adjustment platform and method is also provided. The height adjustment platform includes a first working table, a bottom bracket, a lifting arm, a driving mechanism configured to drive and lock the lifting arm, and a control switch configured to control the driving mechanism; two opposite ends of the lifting arms are separately coupled to the first working table and the bottom bracket, the driving mechanism is coupled to the lifting arm, and the angle is formed between the driving mechanism and the lifting arm.