Liquid refractive index is one of the important optical parameters ,and the measurements of whichare significant in the fields of food production identification ,optical processing,etc. A rotating fine tuning stageis installed on the optical shock absorption platform based on a portable Michelson interferometer.The formulafor calculating the refractive index of the liquid is obtained by considering the changes in the optical pathdifference between the container wall, the measured liquid , and the air after rotation. Compared with the valuesby the Abbe refractometer,  the experimental results show that the average relative errors of water, glucosesolutions of different concentrations , and sodium chloride solutions of different concentrations are respectively1.1%,3.3% and 2.0%, with a maximum error of 5.9%.lt provides a feasible method for measuring therefractive index of liquids,and it can also be used as an expanded experiment for Michelson interferometer, which is of great significance for cultivating undergraduate students’ innovative ability.