Isostearic acid is a kind of chemical intermediate with a wide range of applications.Briefly,the applications of isostearic acid in various fields are introduced in terms of physical and chemical properties,and the main domestic and international preparation methods of isostearic acid and its reaction principle are reviewed,involving hydrogenation,chemical synthesis,and microbial fermentation,etc.In addition,combining with several preparation methods,the process optimization,and the way of sustainable development are discussed in depth.