Inspired by the structure and function of spider hair receptors, a simple harmonic vibration sensor with Symmetrical Electrode Metal-core Piezoelectric Fiber (SMPF) was designed and fabricated. The fiber body was prepared by extrusion-stretch method, and the symmetrical conductive adhesive was used as the external electrode in the longitudinal surface. After polarization, the simple harmonic vibration sensor with the SMPF was prepared. Based on the piezoelectric equation and the vibration theory, the theoretical model of harmonic vibration sensor with the SMPF based on a cantilever beam structure was established, and the relationship between the sensor signal and the angle and amplitude of simple harmonic vibration was analyzed. The SMPF was fixed on a substrate, and an experimental system was built. The response of the sensor to simple harmonic vibration was tested and the theoretical model was verified. The results show that the sensor with the SMPF can accurately sense the frequency of harmonic vibration, the sensor signal is linear related to the amplitude of simple harmonic vibration, and has an "8" shape relationship with the direction. Moreover, the resonance frequency of SMPF is 15.6 Hz, and the sensitivity is 0.019 pC/mm. In conclusion, the sensor with the SMPF can measure the frequency, amplitude or the direction of simple harmonic vibration and has prospect for engineering applications.