A high resolution Stokes spectrum reconstruction method for channeled spectropolarimetry is proposed. A forward model matrix is constructed according to the principle of the interferometer. The elements are arranged using the phase terms of the two retarders and a solving matrix is obtained. The polarization spectra are recovered by the interferogram and the solving matrix using the least squares method. In addition, the forward model matrix can be replaced by a random matrix for a wider application. The new method does not separate the spectrum by windowing, avoiding the aliasing among channels.