Quinoa (Chenopodium quinoa Willd.) has gaining wider attention for its well-balanced nutrition in recent years. As the main ingredient of quinoa grain, starch accounts for more than 50% of the dry weight, which plays an important role in defining the functions and properties of quinoa-contained products. Quinoa starch has smaller granules (1~3 μm) and lower amylose content, compared with other grains. Its amylopectin contains a larger amount of short chains and super-long chains. In terms of nutrition, quinoa starch contains a higher proportion of slow-digesting starch (SDS), indicating its possibility of being applied to produce processed food with low glycemic index. Furthermore, quinoa starch has many applications within and outside of the food industry. To provide theory to support the application of quinoa in different industries, this paper reviewed quinoa’s composition, starch structure and related properties.