Diamond-like carbon (DLC) films were deposited by the Unbalanced Magnetron Sputtering(UBMS) technique which was under the conditions of bias 80V, target current 110A, argon flow 200SCCM, excitation current 100A; experimental platform was built for Laser-induced damage threshold(LIDT). The DLC films was irradiated by the laser (Wavelength 1046nm, pulse width 10ns, laser energy from 0.75mJ/cm2-2.60J/cm2), we got the LIDT of the DLC films is 1J/cm2. The whole physical process from slight burning, spalling, crack splashing until the substance damage of the DLC films was observed by 1000 times magnification and interference microscope. Thermal stress is one of main factors that laser injures films.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.