In order to obtain the status information of the workpiece stably under the working environment, the method of multi-fiber Bragg grating (FBG) network monitoring was adopted, and the multi-fiber grating sensors were distributed on the tooling of the assembly structure. On the basis of obtaining the real-time strain field data of the sensitive positions, the difference was analyzed. The function relationship between the assembly error and the strain field distribution, and the appropriate correction parameters were given. The results show that when 100N stress is applied to the workpiece, the maximum deformation value in the x-axis direction is 0.86mm, and the maximum value in the y-axis direction is 0.69mm; compared with the standard measurement data obtained by laser scanning, it can be seen that the test on the x-axis. The average error of the deformation value of the sensitive position is better than 4.7%, and the average error of the deformation value of the sensitive position tested on the y-axis is better than 3.9%. It is feasible to use optical fiber sensing to realize intelligent correction of the assembly process, and it has good linearity and repeatability in the entire test range, which can improve the effect of intelligent assembly control.