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Acidic ionic liquids (ILs) are used as promising and environmentallyfriendly catalysts for levulinates synthesis, which can replace the sulfuric acid owing to their beneficial characteristics such as high catalytic activity, high selectivity, low corrosion of equipment and ease of recycling. Eight different acidic ILs were examined as catalysts in the synthesis of ethyl levulinate (EL) from carbohydrates with ethanol. Among them, the cations of ILs were imidazole, pyridine and triethylamine salts, and the anion ions were inorganic acids and organic acids. The structures of ILs were confirmed by 1H NMR and13C NMR. All of the ILs exhibited excellent thermal stability over 200℃ through the TG-DTG. The acidity of the ILs was investigated by determining the Hammett acidity functions under UVvisible spectroscopy by using 4nitroaniline as indicator. The introduction of a SO3H group into the IL greatly increased its Brnsted acidity. Anions of ILs had a great influence on the acidity of ionic liquids, and cations with imidazoles were more acidic than pyridine and triethylamine salts. It was found that the \[BmimSO3H\]HSO4 showed the best catalytic activity among all the ILs. The activity of catalytic synthesis of EL was closely related to the Brnsted acid. The highest EL yield of 5679% was obtained for the reaction carried out at 170℃ for 60min with 2mmol \[BmimSO3H\]HSO4 as catalyst and using glucose as the substrate. Furthermore, the ILs remained high activity and stability after reused for 5 times. On the whole, \[BmimSO3H\]HSO4 had stable structural properties in the process of catalytic alcoholysis of carbohydrates into EL, showing a better catalytic conversion efficiency.