Based on the theoretical analysis of the electron hologram, a spatial filtering method to avoid the overlap of the digital reconstructed images of electron hologram is proposed. In this method, we make Fourier transform of the detected electron hologram and filter the obtained spatial spectrum, then generate a new electron hologram by making inverse Fourier transform of the filtered spatial spectrum. The overlap of the reconstructed images of electron hologram is avoided when the obtained new hologram is digitally reconstructed with the usual digital method.