Through detecting the orthogonal curvature of the structure surface to reconstruct flexible plate structure has a significant meaning for active monitoring of aerospace key structure. The plate structure is first decomposed into several surface patches, and then, based on the quadratic equation the surface model is established. The nonlinear equations is created through the analysis of surface patches， boundary constraint conditions. For each patch, the nonlinear equations are solved by using single rank inverse Broyden quasi Newton method to obtain the parametric equation of the surface patch. Through the recursion, the patches can be spliced and it can realize the surface reconstruction. Finally, simulations are carried out in the Mat LAB environment and the experimental results show that the surface fitting algorithm can effectively reconstruct the large deformation surface, so it is feasible for space surfaces reconstruction.