The invention relates to a method for preparing an organic and inorganic composite phase-transition material. The method comprises the following steps: firstly, inorganic porous minerals are added into a reaction kettle; and secondly, the reaction kettle is vacuumized and injected with an organic material and then pumped into the state of negative pressure, and the temperature and the stirring speed are required to be adequately controlled during the reaction process. The method takes the inorganic porous mineral materials as a carrier for vacsorb of organic phase-transition materials which accord with the phase-transition requirements; the composite phase-transition material product prepared has the characteristics of no leakage, inflaming retarding, high phase-transition potential, easily controllable phase-transition temperature and so on; and the preparation method has a simple technology and low cost, has no secondary pollution, and is suitable for flow production and industrial production.