Potassium sorbate is the potassium salt of sorbic acid  PH=8, chemical formula CH₃CH=CH-CH=CH-CO₂K. It is a white salt that is very soluble in water (58.2% at 20 °C). It is primarily used as a food preservative (E number 202). Potassium sorbate is effective in a variety of applications including food, wine, and personal care products. While sorbic acid is naturally occurring in some berries, virtually all of the world's production of sorbic acid, from which potassium sorbate is derived, is manufactured synthetically.

Potassium sorbate is used to inhibit molds and yeasts in many foods, such as cheese,  yogurt, dried meats, apple cider, soft drinks and fruit drinks, and baked goods. It is used in the preparation of items such as maple syrup and milkshakes served by fast food restaurants . It can also be found in the ingredients list of many dried fruit products. In addition, herbal dietary supplement products generally contain potassium sorbate, which acts to prevent mold and microbes and to increase shelf life. It is used in quantities at which there are no known adverse health effects, over short periods of time. Labeling of this preservative on ingredient statements reads as "potassium sorbate" or "E202".

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