We analyze the valence and electronic shell configuration characters of all damageresistant dopants found in LiNbOs crystals u p to now. We show that all damage-resistant dopants have only one valence state. We also show that the electronic shell configurations of these damage-resistant ions are filled fully, as are the cases of the inert elements. n o m this point of view, we conclude that the anti-site NbLi should be involved in the charge transport process, while the Li vacancy V L ~ is not involved in the charge transport process. It also can give us some insights about how t o select a damage-resistant dopant for LiNbOs crystal.