Abstract: The aim was to explore the effects of anthocyanin accumulation in the aerial stems of Panax notoginseng on the cold resistance of P. notoginseng. The soluble protein and malondialdehyde (MDA) contents and the antioxidase specific activities in the leaves of one-year-old P. notoginseng plants with purple and green aerial stems under the low temperature stress simulated by icy water were studied. The results showed that, under the low temperature stress simulated by icy water, the soluble protein contents and the specific activities of the catalase (CAT) in the leaves of one-year-old P. notoginseng plants with purple and green aerial stems, and the MDA contents in the leaves of the green aerial stem plants all increased, the specific activities of the peroxidase (POD) and superoxide dismutase (SOD) in the leaves of the purple and green aerial stem plants, and the MDA contents in the leaves of the purple aerial stem plants all decreased. Moreover, the increasing degrees of the soluble protein contents and CAT specific activities in the leaves of the purple aerial stem plants and the decreasing degrees of the specific activities of POD and SOD in the leaves of the green aerial stem plants were both much larger. When the icy water treatment terminated, the soluble protein content, and the specific activities of the POD and SOD in the leaves of the purple aerial stem plants were higher than those of the green aerial stem plants, whereas the CAT specific activity and MDA content in the leaves of the purple aerial stem plants were slightly lower than those of the green aerial stem plants. However, the differences of the contents of soluble protein and MDA and the specific activities of three antioxidases of the purple and green aerial stem plants did not reach the significant level. Thus, the anthocyanin accumulation in the aerial stems of P. notoginseng was good for the cold resistance of P. notoginseng.