Abstract: Characteristics of reducing agents commonly used in industrially producing chlorine dioxide were introduced with comparison.Research progress in new reducing agents，such as sulfur compound，polyalcohol，organic acid，carbohydrate， urea，and glyoxal for the preparation of chlorine dioxide by sodium chlorate process was summarized.Reaction mechanism of organic reducing agents，methanol and glyoxal，in preparation of chlorine dioxide was discussed.It was pointed that decreasing production cost by using combined reducing agent as well as preparing two useful products simultaneously by using organic reducing agent is the tendency of reducing agent development.

Key words: sodium chlorate, chlorine dioxide, reducing agent