Great attention has been paid to the biodegradable plastics based on renewable resources(such as starch, cellulose and protein), which is one of the important trends in the development of the degradable plastics industry. Due to its wide source, low cost and biodegradability, natural starch is widely used in the preparation of starch plastics and is used in agriculture, food, medicine and packaging industries, which is expected to replace petroleum-based derived polymers. Starch molecules contain a large amount of hydroxyl groups, which easily form intermolecular hydrogen bonds and intermolecular hydrogen bonds, so as to affect their processing. Adding plasticizer to destroy the crystalline structure of starch can produce thermoplastic starch, but the poor mechanical properties of thermoplastic starch are the primary problem affecting its performance. In recent years, extensive research has been carried out at home and abroad in an attempt to enhance its mechanical properties. In this paper, based on the different classification of thermoplastic starch materials, and with the emphasis on the way to improve the mechanical properties and the mechanism, the research work in recent years to improve the mechanical properties of thermoplastic starch materials is summarized. In addition, the related factors affecting mechanical properties and the ways to improve are introduced, and the key research in this field is also summarized and prospected.