This paper reports a novel integrated optics microdisplacement sensor which has been fabricated in our Labs, based on S. Honkanen s proposal. The NA approach is firstly used for ca]culating the characteristics of the sensor and all the performances of the device are measured. The theoretical analysis and experimental results are in agreement basically. Several ways to improve the sensitivity of the device are presented. The sensor could be used in a wide area, such as vibration, acceleration and acoustic sensing etc.