The present work extended the knowledge on the binding and complexation of humic substances( humic acid or fulvic acid) and hematite by Fourier transform infrared spectroscopy( FTIR). The FTIR data gained gave the consist evidences by two different sampling preparation methods that the interaction mechanism between humic substances and hematite was mainly conform to the ligand-exchange involving carboxylic functional groups of humic substances and the surfaces sites of hematite. The present method, although associated with some uncertainties, provided an opportunity to increase the knowledge in this field.