Space-charge field is considered as an important factor determining photorefractive efficiency of polymer composites. Recently, we proposed a simple method which can measure the space-charge field built in photorefractive materials. Six polymeric photorefractive composites with different electron acceptor as a photosensitizer were prepared to vary the photo-charge generation efficiency and consequently to vary the space-charge field only. We investigated the dependency between photo-charge generation efficiency, photoconductivity, and space-charge field.