Based on Rsoft software, the tapered fiber evanescent field distribution is simulated, and the reason for the nonreciprocity of micro- resonator excited by tapered fiber is analyzed in theory. Optical fiber fused silica microsphere cavity is used in the experiment. Through high precision three dimensional adjustment along the fiber direction, test points are selected after moving the same distance and microsphere cavity resonance spectra are recorded under the case of forward and converse transmission of light, getting the regular pattern of non-reciprocity of the resonance spectral parameters with the variation of evanescent field. By calculating the frequency discrimination curve of microsphere cavity, the influence of non- reciprocity on the dynamic range and sensitivity of gyroscope is got, and suppression methods are proposed.