Abstract: A high accurate SOI optical waveguide Michelson interferometer sensor for temperature monitoring has designed and analyzed in this invention. According to the numerical analysis of power reflective spectra of waveguide Michelson interferometers, the temperature sensing of waveguide SOI Michelson interferometer sensor can improve at least 20 times than fiber Bragg grating temperature sensor. Moreover, the SOI Waveguide interferometer sensor we designed presents high sensitivity than pure single waveguide Bragg grating sensor and fiber Bragg grating sensor by adjusting the length of the two interferometric arms. The full wavelength half maximum (FWHM) of our designed SOI optical waveguide Michelson interferometer can be narrowed much smaller than fiber Bragg grating and waveguide Bragg grating sensors for sensitivity improvement. The invention of this optical SOI waveguid sensing devices shows promising results for developing integrated OEIC sensors in the future.