Abstract: The present invention relates to a method enabling the freshness of vegetables to be easily maintained by increasing the germanium content of vegetables and is characterized by comprising the treatment of the surfaces and/or inner parts of vegetables with an organic or inorganic germanium compound by a suitable method. In this case, the organogermanium compound is, for example, carboxyethylgermanium sesquioxide, and the inorganic germanium compound is, for example, germanium dioxide. It is possible to treat vegetables with an organic or inorganic compound in the state of an aqueous solution and the methods available include one in which vegetables are impregnated or are sprayed with the aqueous solution so that the germanium compound acts on the surfaces of the vegetables; and another in which the aqueous solution is absorbed by the roots of the vegetables so that the germanium compound acts on their inner parts.