Abstract: In order to ensure the proper operation of optical instrument in harsh environment, detailed engineering analyses are frequently needed. Traditional analysis, integrated analysis and unified analysis for optomechanical systems were investigated. Their operation principles, processes, as well as their advantages and disadvantages are described. Some issues on thermalelastic analysis and the fitting of Zernike polynomial in integrated analysis are addressed. The problems need to be considered in unified analysis are summarized. Based on the tradeoff investigation of the three methods, the development trend of the optomechanical analysis methods is forecasted. It is concluded that integrated analysis is the most frequently used opto-mechanical analysis method in the long run.