The interference results are associated with the force and temperature fluctuation in Taiji-1. To obtain the maximum effect of these noises, the coupling noise analysis of the force and temperature on the interferometer is discussed. First, the impact mechanism of force and temperature fluctuation is introduced. Then, the mechanical and optical simulation based on a simplified model are performed in turn to get the relationship between the noises and the interference results. The final relationship indicates that coupling effect of the force and temperature fluctuations on the interference is a superposition of the results from the situation with only force or temperature fluctuation, corresponding to the respective frequencies. Based on the relationship, the final amplitudes of interference results caused by the force and temperature fluctuation are 111pm@0.1Hz and 87.47pm@0.05Hz, respectively, when the corresponding noises are 50µN@0.1Hz and 1.7mK@0.05Hz in the proposed simplified model. © 2021 SPIE.