An object of the present invention is to provide an antifreeze solution which is used by adding it to a heating medium of a heat exchanger or a radiator coolant for an internal combustion car engine, which can be used to prevent the icing of road surfaces, which is easy to use and environmentally friendly, and which does not contain environmentally harmful substances such as ethylene glycol so that it can be easily treated for disposal after use. Another object of the present invention is to provide an antifreeze solution which contains water as a main component and glycerin. The undiluted antifreeze solution does not freeze even at −20° C. or less at normal pressures and is composed of components at a certain ratio.