Abstract: An analytical investigation of the large deflection behaviour of rectilinear orthotropic circular plates under uniform means of analyzing the flexural stiffness of the plate, a non-axisymrnetrical flexural deflection is founded. Galerkin's procedure is used to solve one of the von Karmantype large deflection equations and an exact solution is obtained for the rest equation.The solution to the plates with three kinds of orthotropies, Glass/EPoxy, Boron/Epoxy and Graphite/Epoxy, is found under the clamping, radially immovable boundary conditions.The influence of the non-axisymmetrical def leation is investigated. The results show as follows.