Oligochitosan(OCH) is a water-soluble low carbohydrate polymer consisting of β-1,4-linked 2-acetamido-Dglucose and β-1,4-linked 2-amino-D-glucose units. OCH has been universally used in the fields of agriculture, food and medicine. Antifungal activity of OCH on the growth of pathogens causing postharvest diseases of fruits and vegetables, and how its application is affected by molecular weight and concentration are reviewed in this paper. Inhibitory effect of OCH on postharvest diseases, and the effect of O...