Abstract: This article deals with the annual growth rhythm of Ulmus elongata seedlings.The four growth periods were divided for the seedlings by using cluster analyses of series samples.The results showed that the logistic equations were fitted for the growth of height and diameter,the optimum regression equation was found for the growth of seedlings height,diameter and main root,and the relations of each part growth of the seedlings were also revealed.The multivariate regression analysis indicated that the temperature was the main factor in influencing the growth of Ulmus elongata seedlings.