Based on systematically-collected data related to the character “yan 盐” in the writing of the Warring States period, the present paper makes the paleographic argument that the character“ ”in the inscriptions of Chu State slips from Baoshan is just “盐”. This is a character with associative compounds. It is made up of “lu卤” and “min 皿”, meaning making salt by boiling salty water. The exact identification of this character will much contribute to the understanding of the characters for “salt” in other writings of ancient China. The seal “ Xi (Xi) Yan Zhi Xi (徙)盐之玺”, i.e. “Seal of Salt Circulation”, was an official seal used in the course of salt circulation for the purpose to ensure regular salt trade and effective taxation and to avoid the repetition of tax levy.