The present invention addresses the problem of providing an aging inhibitor that is capable of retarding the onset of aging symptoms and prolonging human life and has a high safety.The aging inhibitor according to the present invention, whereby the above problem can be solved, is characterized by comprising, as an active component, a fermented plant product that is a mixture of the following materials (a) to (g):(a) a koji mold-fermented product of one or more kinds of beans and/or cereals selected from the group consisting of barley, black soy bean, red rice, black rice, adzuki bean, job's tears, barnyard millet, foxtail millet and millet；(b) a yeast- and/or lactic acid bacterium-fermented product of one or more kinds of fruits selected from the group consisting of orange, grape, apple, Vitis coignetiae, peach, persimmon, papaya, pear, watermelon, plum, fig, Chinese quince, pumpkin, kumquat, citron, loquat, apricot, jujube, chestnut, Actinidia polygama and Japanese plum；(c) a yeast- and/or lactic acid bacterium-fermented product of one or more kinds of root vegetables and/or potatoes selected from the group consisting of purple fleshed sweet potato, Jerusalem artichoke, carrot, onion, sweet potato, Colocasia esculenta, Japanese yam, radish, red turnip, burdock, lotus root, Yacón, lily bulb, sagittaria, ginger, garlic and turmeric；(d) a yeast- and/or lactic acid bacterium-fermented product of one or more kinds of flower vegetables and/or leaf vegetables selected from the group consisting of cabbage, perilla, mulberry leaf, Houttuynia, Artemisia vulgaris indica, Sasa albo-marginata and dandelion；(e) a yeast- and/or lactic acid bacterium-fermented product of one or more kinds of marine algae selected from the group consisting of kelp, wakame seaweed and mozuku；(f) a yeast- and/or lactic acid bacterium-fermented product of one or more kinds of nuts selected from the group consisting of black sesame, walnut and ginkgo； and(g) a yeast- and/or lactic acid
