Small molecular sugars are a group of sugars with low molecular weight, mainly including monosaccharides, disaccharides, and other oligosaccharides with low degree of polymerization. Small molecular sugars are commonly used as food additives in the food industy, including providing sweetness, improving food texture and optimizeing food processing adaptability. In addition, some small molecular sugars also have unique physiological functions that can be used to regulate the nutritional quality of food. Starch is the most common staple component in food, and starch and its modified derivatives are also widely used as food ingredients in food categories such as sauces, dairy products, beverages, and meat products. The composite system of small molecular sugar and starch is widely used in food. The addition of small molecular sugar has an important impact on the properties of natural starch, and plays an important role in regulating the quality of starch-based foods. This article mainly introduces the common small molecular sugars in food and their effects on the main physical and chemical properties of starch (gel texture, transparency, coagulation, gelatinization, freeze-thaw stability, aging, digestion, etc.), with emphasis on the impact of different types and amounts of small molecular sugars on the properties of starch from different sources. This paper aimed to provide reference for the application of small molecular sugars in starch based foods.