In order to meet the developing demands of subsequent larger scale amplifier and improve the field installation quality of the optomechanical modules of existing amplifier, we analyze the flaws in the structure design of the field installation process device, study the technique flow, accuracy and time-allotment of field installation, construct the function structure tree of the field installation device, and optimize the sub-function and structure integration. Based on these studies, the design sketch of the new field installation device is proposed, which is suitable for the optomechanical modules installation of existing amplifier. In the following, realization process and advantages of the system are further analyzed, the theoretical calculation of key structure, engineering design, sub-functional verification and machine debugging of the new device are carried out before it is used to verify design effectiveness through batch installation mission test of optomechanical modules of existing amplifier. The results show that the new device meets the requirements of the field installation of optomechanical modules of amplifier, the feasibility of its structural design is verfied.