Calcium carbonate is the most widely used inorganic powder filler in plastic industry. Calcium carbonate as plastic filler can improve the physical properties of products, reduce production costs, and play an important role in the manufacture of environmentally friendly plastic materials. Studies have shown that when calcium carbonate is added to biodegradable plastics, the distance between polymers is increased by calcium carbonate particles, the force between polymer chain segments is weakened, the re-crosslinking of macromolecular free radicals is hindered, and the free radical chain breaking reaction caused by photodegradation is accelerated, so as to accelerate the degradation of biodegradable plastics. In buried humid environment, calcium carbonate can also be chemically dissolved, which can be directly used as carbon source by some inorganic nutritive microorganisms. Organic acids produced by microorganisms in the soil, nitric acid and sulfuric acid produced by nitrifying bacteria and sulfide bacteria can further improve the solubility of calcium carbonate. The comprehensive action of various factors can greatly improve the degradation process of biodegradable plastics by calcium carbonate.