Sterols are a kind of steroids in nature. Although they are not in much content, they have high application value. Because it is solid, it is also called solid alcohol, which belongs to macromolecular alcohols. It is the main component of unsaponifiable substance in oil. According to the different sources, sterols can be divided into three categories, namely animal sterols, phytosterols and bacteriosterols. Phytosterol is considered as a mild free radical scavenger, which explains the positive role of phytosterol in maintaining cell membrane stability, inhibiting inflammation, antibacterial, preventing atherosclerosis and anti-cancer. Phytosterol is widely used in medicine, food, cosmetics, feed and other industries. Phytosterol has a wide range of biological functions in medicine and food science. In animal production, scientific use of phytosterol can promote animal growth, improve the health of the body and improve the quality of animal products, which has a positive effect on reducing the cost of breeding and improving economic benefits. As a functional additive, phytosterol has a broad application prospect in feed industry. At present, the mechanism, effective dosage form and dosage, absorption efficiency and application technology of phytosterol in improving animal growth and health have not been fully clarified, and a lot of in-depth research is needed to lay a foundation for its scientific and reasonable application.