Diamond‐like carbon films, prepared by the dual‐ion beam sputtering method on glass substrate, were irradiated by both carbon ions (C+) and hydrogen ions (H+) under the dose of 1×1017ion/cm2and the energy of 114 and 112 keV, respectively. The as‐deposited and the irradiated films were characterized by electrical resistivity, infrared transmittance, and Raman spectroscopy. It showed that the irradiation of both the C+and the H+can lead to the decrease or even the removal of bond‐angle disorder and the increase of thesp2C‐C bond dominated crystallite size and/or number. The irradiation can also break thesp3C‐H bond. But the irradiation of C+can lead to a bigger decrease ofsp3bonds, forming a film containing moresp2bonds, and the induced film was then more graphite‐like. In irradiation of H+, however, the decrease degree ofsp3bonds is smaller and the irradiated film still showed evident diamond‐like characteristics in electrical and optical properties. The different irradiation mechanisms of the two ions on the diamond‐like carbon films are briefly discussed.