The invention provides a freshness prolonging device for foodstuff for prolonging a shelf life of foodstuff by storing the foodstuff in a high electric field atmosphere. The freshness prolonging device for foodstuff includes an electrode plate to be removably mounted on a surface opposed to foodstuff stored in a food storage unit and a power source for applying a high voltage to the electrode plate. The electrode plate is composed of an electrically conductive rubber sheet hermetically sealed with a cover composed of a resin sheet.
