Abstract: Adaptive frequency sampling is expanded into multivariate adaptive sampling method to analyze the electromagnetic characteristics of frequency selective surface (FSS). According to the functional relation of the scattering parameters and multivariable of FSS, the multivariate rational function is modeled. The new sampling points in each dimension are chosen by the areas of highest error. By using the interpolation values of one dimension as the initial values of other dimensions, one-dimensional interpolation is expanded into multi-dimensional method. Combining with method of moment(MOM), the effects of frequency and incident direction on the electromagnetic characteristics of FSS are analyzed. The scattering characteristic of cross cell and rectangular ring cell FSS and pattern of FSS radome enclosed antennas are considered. The results agree well with that of MOM and the computational efficiency is promoted. The validity of the proposed approach is verified.