A height adjustment device, which includes a base, which connects to a main bar of a golf cart, and a sliding block which connects to a handle of the golf cart. There are two parallel arc oriented plates formed on each side of the base, and sliding block on both sides of the location near the opening matching with the corresponding slide guide plate. Movement of the sliding block along the base of the curved guide plate adjusts the angle and position between the sliding block and base. Furthermore, the movement can adjust the angle and position of the handle and the main bar and the overall height of the device. The device is simple, suitable for different groups of people, and may adjust handle height at any time.