In this study, a new and very computational effective method related to electromagnetic scattering from periodic dielectric surfaces is proposed. This method is based on Taylor series expansion of fields on the planes which are below and above of the periodic surface. The fields are represented by Floquet modes with unknown coefficients. Using the boundary condition, series equations are obtained. These series equations can be solved using orthogonality properties of Fourier expansion functions. Thismtransformation makes the problem simple formulation and computational effectively without involving calculation of slowly converging periodic Green's function. The proposed method can be extended for solution of electromagnetic scattering from multilayer periodic dielectric rough straightforwardly. Results and computational times obtained by transform method and those obtained by Method of Moments (MoM) technique are compared. Good agreements are observed in results. It is also observed that transform method needs much less computational time than MoM method. © 2014 Wiley Periodicals, Inc.