The invention relates to a phase change temperature-controlled fuel assembly for a non-combustion type low temperature cigarette and a thermoplastic preparation method of the fuel assembly. Within the free space of an annular cavity formed between a nested inner surface and the outer surface of a fuel element, CO is subject to adsorption and oxidation catalysis on the basis of a thermo-electric effect of tourmaline as well as an electrostatic field effect and an adsorption effect of a spontaneous electrode. According to the invention, the fuel assembly is prepared by virtue of a melt extrusion molding method of thermoplastic powder in combination with a carbonaceous raw material and nested powder, namely the carbonaceous raw material, a nested matrix material and phase change heat storage powder are pre-plasticized and mixed by virtue of a thermoplastic binding agent, and processes of compound assembly melt continuous extrusion, air-cooled consolidation as well as pyrolysis and carbonization are adopted, so that the problems of a water-based paste which is slow to dry in extrusion molding and is deformed in structure are solved through a rapid molding method of quenching and consolidating the thermoplastic material, and the manufacturing efficiency of the fuel assembly is improved.