The present invention prepares glycol antimony through the reaction between glycol and antimony trioxide and during the reaction water is removed constantly to make the reaction proceed forward. The process is one reacting rectification process. The present invention has the advantages of no negative effect of group on the product quality and capacity of preparing product with high solubility, high purity, good color and high activity. The product is used in the polymerization of producing polyphenyl glycol diformate.