Abstract: In this paper, the vigor, physiological and biochemical characteristics of welsh onion seeds were measured regularly by artificial aging（45 ℃,100% RH） and natural aging（room temperature storage）,and studied the change rule of vigor in both two aging process of welsh onion seeds and compared the difference between the two methods.The results showed that the germination rate, germination potential, germination index, vigor index and CAT activity of the artificial aging seeds decreased gradually with the extension of aging time, while the POD activity first decreased and then increased with the extension of aging time.The seed vigor decreased faster in the early aging stage and slower in the later aging stage, but SOD activity and free radical content did not change significantly.The germination rate, germination potential, germination index, vigor index, CAT and POD activities of welsh onion seeds under natural aging condition decreased significantly with natural storage time, indicating that the vigor of seeds was obviously lost.Under the same change of germination rate, the germination potential, germination index, CAT activity and POD activity of naturally aged welsh onion seeds decreased significantly faster than that of artificially aged seeds.The aging law of artificial aging was not completely consistent with that of natural aging, so it could not completely replace the natural aging.