Axis of rotation error on rotary system are significant; such as the spindle radial error motion of a aligner, wire bonder and inspector machine which results in the poor state of manufactured goods. In this paper, the simple stage which consists of one PZT actuator and rotary encoder, is measured and analyzed. The simple rotary stage is measured radial error components by one capacitance type displacement sensor. As the result of experiment, the paper discusses several issues that must be considered when designing rotary stage driven by PZT.