The adsorption of a membrane protein of flagellar FliF and its derivatives onto chemically modified surfaces has been studied. FliF proteins are known to aggregate into the intricately shaped MS ring of the flagellar basal body, a major part of the flagellar motor. This protein ring plays the central role in interactions with other components necessary for the flagellar function. However, at the molecular level, the understanding of such specific interactions between proteins has been limited. The preparation of well-defined protein samples suitable for physical-chemical characterization is essential, as well as appropriate methods for characterization. A combination of atomic force spectroscopy and Fourier transform-infrared spectroscopy is employed effectively to investigate the adsorption modes of the proteins on variously modified mica surfaces. FliF protein rings have been found to be oriented on both surfaces of unmodified and amine-functionalized mica through a specific interaction between the FliF rings and the substrates. The binding site of a FliF ring to the unmodified mica surface is probably located in the C-terminal residues, while that to the amine-modified mica is probably found in the N-terminal residues.