The potential reactions between natural polysaccharides and iodine and their products have been explored for a long time. Due to the complex factors that can influence these reactions, a clear-cut mechanism has not yet been developed. Starch-iodine complexes, especially the amylose-iodine complex, are the most investigated of the polysaccharide-iodine reactions, and the study of this reaction can be used as a basis for the investigation of other polysaccharide-iodine reactions. In this paper, significant aspects of the reaction were introduced, including the influence of the polysaccharide structure on the properties of the resulting complexes, the relationship between the concentration of CaCl₂ and formation of the final products, as well as the form of the polyiodides in these complexes. The interior structure and the surface morphology of the complexes were discussed, along with the progress in research related to this reaction.