Plukenetia volubilis L. stem leaf extract capable of delaying senescence as well as preparation method and application of extract

The invention provides a plukenetia volubilis L. stem leaf extract capable of delaying senescence as well as a preparation method and an application of the extract in the aspects of cosmetics, health food and the like. The invention also relates to a cosmetic composition which is used for resisting oxidation, preventing skin aging and removing wrinkles and contains the plukenetia volubilis L. stem leaf extract as an active ingredient. The plukenetia volubilis L. stem leaf extract has inhibition activity on elastinase, collagenase and hyaluronidase and has significant effects in collagen secretion promoting experiments. The usage amount of the extract in health food or anti-aging cosmetics can be 0.01wt%-100wt%.