A certain component is a kind of multilayer narrow gap container. To test the vibration of slab induced by flowing water at high speed in this component, a shielded eddy current sensor is designed based on the eddy current principle. The coil parameters of the probe and the structure parameters of probe’s shell are optimized for the proposed shielded eddy current sensor. The assembly and debugging, as well as the calibration of the third party, are performed. The test results show that: the proposed shielded eddy current sensor, which has no interference to the flow field and no breakage to the structure of the device, can realize the vibration test of slabs with narrow gap reliablely and efficiently.