Desulfurization of thiophene in coking benzene with n-butanol as an alkylating agent over SO42-/Fe2O3 solid superacid at 353 K and atmospheric pressure was investigated. The acidity of the catalyst was measured by temperature-programmed desorption (TPD) of ammonia, and the result confirms that the SO42-/Fe2O3 catalyst has a high acid strength. The sample after reaction was detected by gas chromatography-mass spectrometry (GC-MS), and the results show that thiophene has been removed completely.