The experiment of measuring the coefficient of thermal expansion by Michelson interferometer is optimized based on the microcontroller technology.Firstly, the automatic recognition of Michelson’s interference fringe is realized by using the fringe recognition system ,then the automatic temperature measurement is realized by using the temperature detector,and finally the data calculation of the coefficient of thermal expansion is realized by computer programming.By introducing the microcontroller and computer programming technologies into the university physics experiment,the visualization of the experimental data and the intelligent calculation are realized, which makes the measurement and calculation of the coefficient of thermal expansion more convenient and faster.At the same time,the application of Michelson interferometer is expanded by applying the large object experimental equipment to the actual experiment.