Abstract: There is provided a method for aligning a spindle of a machine tool, the spindle having a longitudinal axis and being rotatable about the longitudinal axis. A trial mounting of the spindle is performed, comprising mediately or directly attaching a bearing surface of the spindle to a support surface of the spindle housing. An actual deviation of the spindle is detected. A wedge-shaped adjustment disc is selected, depending on the detected actual deviation. The adjustment disc is arranged between the bearing surface of the spindle and the support surface of the spindle housing in a defined rotation orientation so that the adjustment disc at least partially corrects the actual deviation.