This paper presents an extension of Multi-layer Moving Plate Method (MMPM) for static and free vibration analyses of functionally graded (FG) sandwich plate resting on a viscoelastic foundation. The FG sandwich plate is composed of two parallel FG plates, in which upper plate is connected with lower plate by a viscoelastic layer and the lower plate rests on a viscoelastic foundation. The convergence and accuracy of this method are validated by comparing the results obtained from this study with other published results. Next, several numerical results are presented to examine the static and free vibration behaviors of FG sandwich plate with various volume fraction exponents, boundary conditions, geometric parameters, connected layer and foundation stiffness.