A new three dimensional electronic speckle pattern interferometry (ESPI) system is constructed by three ESPIs through a large shearing device and a PZT phase shifter used as reference. Independent dispelacement fields (i.e. field u, v and w) can be obtained through the system with phase shifting technique and image processing. This new technique includes three lasers as light source, a PZT phase shifter which can push reference plane to change optical path of reference light. A large shearing Wollaston prism is placed in front of CCD camera to make interference between object wave and reference wave. This system is used in measuring parts of diesel engine. Three dimensional displacement fields around the hole of the main axle are obtained.