Carbonaceous thin-film electrodes were modified by nitrogen trifluoride (NF3) plasma, and surface-modified carbonaceous thin-film electrodes were obtained and investigated by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy (AES). Their chemical composition, degree of fluorination, and chemical bonding were investigated. The effects of surface modification on the anode reaction of lithium-ion batteries were examined. The electrochemical properties of the resultant thin-film electrodes were investigated by cyclic voltammetry using a three-electrode electrochemical cell. The cyclic voltammograms showed that the fluorine atoms on the surface suppressed the reductive decomposition of ethylene carbonate.