The scattering and absorption characteristics of light by spherical particles are often analysed based on the classical Mie scattering theory.In this paper，we study refractive index sensor of multi-mode based on the Mie scattering and its extension theories. Based on the Mie scattering theory, the light extinction, scattering, absorption cross-section, and absorption efficiency associated with the spherical particle can be calculated.The structure that we design has a long wavelength possesses a higher power than that with a short wavelength.Also,the structural parameters induces a red-shift in the resonance spectrum. Lastly,the results of multi-mode are obtained: the transmittance of modes 1, 2, and 3 vary within the ranges 0.43–0.67, 0.61–0.46, and 0.26–0.5, respectively; the figures of merit of modes 1, 2, and 3 can reach as high as 12, 27.7, and 3.8, respectively; the refractive index sensitivity can reach as high as and . As indicated by these findings, the proposed structure can significantly improve the transmission characteristics of nanodevices. Such a structure holds significant potential for application in the field of on-chip plasma sensing and optical communication.