Polyols are widely distributed in nature, for example in lichens, mushrooms, fruits, lens semen, and some fermented foods such as wine, Japanese sake, or soy sauce. Among them glycerol, sorbitol and mannitol are industrially producted at present and used as chemical of food ingredients due to their specific characteristics. Erythritol, a C4-sugar alcohol, was considered to be used as ingredient of food, chemicals and pharmaceuticals. Moreover erythritol can be chemically synthesized or biochemically produced. However, since a mass production process of erythritol has not been development yet, the chemical, physical and physiological properties have not been studied thoroughly. In this paper polyol fermentation from as a substrate will be described, with emphasis placed on the screening and isolation of microorganisms which produce erythritol in high yield. Furthermore physicochemical and physiological properties of erythritol, and its utilization for food and other products will be discussed.