The invention relates to a heat stabilizer containing liquid 
barium and 
zinc, a preparation method thereof, and application thereof. The heat stabilizer consists of the following components in percentage by weight: 10%-30% of liquid 
carboxylate with the percentage by weight of 
barium as 5%-20%, 5%-30% of liquid 
carboxylate with the percentage by weight of 
zinc as 2%-15%, 10%-40% of composite 
phosphite ester, 1.5%-5% of beta-
diketone, 0.5%-3% of antioxygen1010, 10%-40% of DOP (dioctyl 
phthalate), and 1.0%-5% of odourless 
kerosene. Liquid 
carboxylic acid metallic 
soap and auxiliary stabilizer are adopted to exert the synergistic effect, excellent 
heat stability and excellent initial-stage 
dyeing property and transparency are achieved for PVC (
polyvinyl chloride) soft products, the production process is simple, only two steps are required, the production cost is low, the investment is low, and the heat stabilizer containing liquid 
barium and 
zinc is applicable to large-scale industrial production.