A graphene transparent electrode might be used in industry in the near future instead of indium tin oxide (ITO). For patterning of ITO, the maskless laser process was reported as a simple and fast process. In this paper, effects of ultra-violet laser irradiation to graphene on SiO 2 /Si are investigated. The experimental results show that the threshold thickness of graphene for complete removal from the SiO 2 /Si substrate by laser irradiation is approximately 10nm. Thinner graphene layers than the threshold thickness were removed by laser irradiation with a power density of larger than approximately 3.5MW/cm 2 . The mechanism for the observed complete removal of graphene should be ejection due to the supersonic elastic vibration of the substrate caused by pulsed laser irradiation.