Magnetic domain structure on a silicon iron (001) surface has been observed using a new scanning electron microscope (SEM), in which image contrast was obtained by using spin polarization of secondary electrons. From this image and an absorption current image of the same area, it has been confirmed that the domain structure image is not influenced by surface morphology. This represents an improvement over conventional domain structure observation methods. This new SEM will be greatly improved also as for the resolving power compared to conventional reflection methods, when used in conjunction with a proper field emission gun.