The separation of mixtures of avidin, streptavidin, and neutravidin were investigated by using combinations of C8phase capillary and some surfactants such as anionic, cationic, zwitterionic, nonionic surfactants, polyvinyl alcohol (PVA), and hydroxyl cellulose (HEC) polymers. The combination of zwittergent 3 – 14 and C8phase capillary gave the best separation of avidin and its relatives. The satisfactory reproducibility of the peak height and the migration time were achieved by this system. The complete separation of the mixture of avidin, streptavidin, neutravidin, and other three basic proteins was achieved with sharp peaks in pH 5, 7 and 9 of running buffers.