Abstract: We propose a new numerical homogenization method based upon the edge multiscale method for time-harmonic Maxwell equations in heterogeneous media with large wavenumber. Numerical methods for time-harmonic Maxwell equations in homogeneous media with large wavenumber is very challenging due to the so-called pollution effect: the mesh size should be much smaller than the reciprocal of the wavenumber to obtain a solution with certain accuracy. It is much more challenging for the case with heterogeneous media that occurs often in the practical applications, such as the simulation of metamatrial, since one has to resolve the heterogeineouty for a reasonable numerical solution. We devise a novel approach that do not to resolve the heterogeneouty in the coefficient and has a mesh size linearly depends on the reciprocal of the wavenumber, which has a first order convergence rate. Extensive numerical tests are provided to verify our theoretical findings.