For the first time, we report a spin filtration operation considering an antiferromagnetic helix system, possessing zero net magnetization. Common wisdom suggests that for such a system, a spin-polarized current is no longer available from a beam of unpolarized electrons. But once we apply an electric field perpendicular to the helix axis, a large separation between up- and down-spin energy channels takes place, which yields a high degree of spin polarization. Our analysis may provide a route of getting conformation-dependent spin polarization possessing longer range hopping of electrons, and can be generalized further to different kinds of other fascinating antiferromagnetic systems.<\/p>\n