When a white light interferometer is applied to 3D surface microcosmic topographic measurement, the measuring accuracy is effected by the hysteresis and creeping phenomenon generated by the piezoelectric actuator seriously. Therefore, this paper proposes a method to improve the displacement accuracy of the reference mirror along the optical axis direction. The piezoelectric actuator is given, and its displacement detecting circuit, PID closed loop control algorithms, and creep compensation control are studied. First, displacement detecting circuit is established by a position sensitive device and an optical lever, by which the piezoelectric ceramic micro-displacement can be fed back to control the system, then the PID closed-loop control algorithm is established. Furthermore, the creeping characteristics of piezoelectric ceramic is discussed during the measurement. In order to eliminate the creeping phenomenon and improve measurement accuracy, the “voltage creep” compensation model is proposed. Finally, an integer control system based on PID closed-loop control and creep compensation control is established. The micro-displacement of the piezoelectric actuator is measured by a high-precision XL-80 laser interferometer under the two cases of PID closed-loop control and integer control. Experimental results indicate that the displacement error for the former is 0.007 μm, and that for the latter is 0.005 μm,respectively. This method reduces the influence of hysteresis and creeping on measurement results, and meets the requirements of three-dimensioned shape measurement for high accuracy.