Abstract: Cyclodehydration of hexaric acid is a promising route for the industrial scale production of 2, 5-furandicarboxylic acid (2, 5-FDCA). Hexaric acids including gluconic acid, galactaric acid and mannaric acid are isomers with different spatial structures. The effects of hexaric acid sources on the kinetics of cyclodehydration reaction to prepare 2, 5-FDCA were studied. The result shows that hexaric acids have certain effects on cyclodehydration and the yield is in order of: glucaric acid-1, 4-lactone>calcium saccharate> potassium bisaccharate >galactaric acid. Compared with galactaric acid, calcium saccharate has higher yield and milder reaction condition. The degradation activation energy of calcium saccharate, generation activation energy of 2, 5-FDCA and activation energy of side reactions are 91.7, 87.7 and 98.2 kJ·mol^-1, respectively, while those of galactaric acid are 95.2, 92.2 and 98.3 kJ·mol^-1, respectively. Therefore, calcium saccharate has lower degradation activation energy and 2, 5-FDCA generation activation energy than these of galactaric acid, and the gap between the activation energy of the main and side reactions is greater. These results suggest that calcium saccharate is more conducive to produce 2, 5-FDCA with sulfuric acid, which provide basic data for the cyclodehydration of hexaric acid.