The invention relates to PVC heat stabilizer, in particular to heat stabilizer applied to decoration of PVC materials, a preparation method and application thereof. The barium-zinc liquid stabilizer is prepared from the following components in percentage by weight:, 20.0 to 35.0 percent of sodium iso-octoate, 10.0 to 15.5 percent of oleic acid, 8.5 to 12.8 percent of barium monohydrate, 1.0 to 5.0 percent of zinc oxide, 5.0 to 10.5 percent of diethylene glycolmonobutylether, 1.0 to 3.0 percent of antioxidant 1010, 1.0 to 4.5 percent of bisphenol A, 1.0 to 3.0 percent of beta-diketone, 5.0 to 10.5 percent of anti-separation agent, and 20.0 to 35.0 percent of DOP, wherein the total amount of components is 100 percent. The invention solves the problem that products have foreign smell based on raw materials, simplifies the production process by a one-step synthesis method, has more convenient operation, and has the effects that: firstly, the stabilizer saves energy consumption and reducing pollution; secondly, the stabilizer has high value advantage compared with international products with the same function and has better competitive force; and thirdly, the stabilizer belongs to green and environment-friendly product, and has strong vitality.