Abstract: The invention relates to a method and system for obtaining a liquid fuel from waste from plastic or polymer material, which, according to its structure of steps and devices, allows lower energy use with respect to the disclosure in the prior art. In addition, by means of the method and system, the load of plastic and polymer waste in the environment, mainly waste that may be destined for landfill, is reduced. Thus, in addition to waste material being reduced, energy is recovered at highly favourable cost, as a result of the layout of electric heating elements for delivering the energy or heat needed to correctly transform the waste material, in short processing periods and with the adaptability of being able to be formed from moveable, transportable systems, even large industrial installations.