Abstract: Based on the general six-degrees-of-freedom plate theoryand the accurate stress analysis, using the variational principle and theequivalent strain theory in damage mechanics, the three-dimensionalnon-linear equilibrium differential equations for the interlaminarstresses of laminated plates with the damage effect of the intra-layers andthe interlaminar interface are derived in the framework of the theory ofelasticity. With a simply supported laminated beam-plate withdamage as an example, an analytical solution is presented by using finite differencemethod to obtain the interlaminar stresses.