A process for forming a glass sheet, which is a process for continuously forming a glass sheet, and which comprises a step of introducing a vapor film-forming agent, which is not vapor at least around room temperature and which is vapor at a temperature above the glass transition point of the glass, into a support composed of a structure or a material capable of internally containing liquid, and a step of sliding the support and the glass of which temperature is above the glass transition point against each other via a thin layer of a vaporized vapor film-forming agent.