Starch is of the most important carbohydrates in human diets for maintaining normal body's energy metabolisms. However, due to the increased number of chronic diseases worldwide, the further study of the starch property in the dietary formula becomes essential for revealing its association with preventing or intervening the occurrence of such diseases as diabetes, obesity, intestinal diseases and even cardiovascular diseases. Considering that different starches demonstrate different digestion property based on their individual structural characteristics, in particular, the existence of resistant starch (RS) attracts much more interests recently because of its being a major producer of short-chain fatty acids followed by gut microbial fermentation. Furthermore, the understanding of the interaction between RS and microbiota in the gut and its substantial influence on the regulation of diabetes, kidney, disease hypertension and others is still being under investigated. Therefore, this chapter summarized the fine structure of starch, resistant starch structural characteristics, formation and preparation of resistant starches and their corresponding physiological property.