Abstract: Large deflection of cylindrically orthotropic circular plates under combined transverse and in-plane loads has been studied in this paper. The Galerkin's Technique was used with Chebychev's multinomial expansion as a trial function. The basic equation is the Vonkarman type of large deflections for plates. Some special examples are compared with those of references. They arein good agreement. Some conclusions are of benefit to an efficient design of circular plates.