Nanometer-thick room-temperature ionic liquids (RTILs) have been studied for potential application as media lubricants for heat-assisted magnetic recording (HAMR) in the hard disk drive (HDD) industry. The RTILs containing fluorinated anions are readily solvable in Vertrel XF solvent and can be applied on the media by dip-coating, which is compatible to the current industry process. The thermal stability, topography and tribological performance of the RTILs nanofilms have been characterized by thermogravametric analysis (TGA), ellipsometry, atomic force microscopy (AFM) and nanotribometry. The experimental results showed that RTILs are thermally more stable than the state-of-the-art media lubricants in HDDs, i.e., perfluoropolyethers (PFPEs) such as diolic perfluoropoly(oxyethylene-ran-oxymethylene) commercially known as Zdol. The lubricant uniformity of most studied RTILs is better than that of Zdol, and no dewetting is observed even when the RTIL nanofilm is as thick as 10 nm. The friction coefficient of subnanometer-thick RTILs is lower than that of Zdol. The structure-property relationship and the possible structure design for the future improvement have been discussed.