The invention belongs to the technical field of chemical engineering, and particularly relates to an efficient composite heat stabilizer for pentaerythritol cerium-based PVC and a preparation method of the heat stabilizer. The efficient composite heat stabilizer is prepared from the following raw materials in weight part: 30-50 parts of pentaerythritol cerium, 10-15 parts of barium stearate, 20-30 parts of calcium stearate, 20-30 parts of a lubricant and 10-15 parts of an auxiliary heat stabilizer. The preparation method comprises the following steps: firstly the pentaerythritol cerium, barium stearate and calcium stearate are added into a reaction kettle for fully mixing, the well mixed material is added into a kneading machine and kneaded for 20-30 minutes at the temperature of 100-120 DEG C, then the lubricant and the auxiliary heat stabilizer are added into the kneading machine, and kneaded and mixed for 30-40 minutes, the material is discharged, and the tabletting, sieving and packing are performed, so that the efficient composite heat stabilizer is obtained. The efficient composite heat stabilizer prepared through the preparation method has the characteristics that the heat stabilizer is difficult to separate out, excellent in stability, low in cost, non-toxic and environmentally friendly, and the raw material is easy to obtain. The preparation method provided by the invention causes no pollution, is low in energy consumption, is scientific, reasonable and simple, and is easy to realize.