Abstract: In order to obtain particular twist angle of composite structure, utilizing the coupling effects of unsymmetric&unbalanced laminate is a considerable approach. An unsymmetric&unbalanced laminate is formed by adding a sub-laminate into the symmetric laminate. How to lay the sub-laminate and what the optimal orientation angle of the sub-laminate is are studied in order to make the most use of coupling effects by nonlinear finite element methods. Test results of honeycomb core sandwich composite laminate simulating the wing-box under the load of aerodynamics demonstrate that the calculating results well accord with the test results and unsymmetric&unbalanced laminates have prospective engineering applications.