Abstract: In order to obtain new varieties which were suitable for the Yangtze River Basin, 4 combinations of Populus deltoides were selected for hybridization. Growth characteristics were investigated which were from the clones of the offspring, to compare the differences of the growth characteristics and growth rhythm in 4 combinations of Populus deltoids. The result of the statistics and analysis showed that: the height and diameter were normal distribution in ZS8×2-7 (P=0.200>0.050), the diameter was normal distribution in 2-2×2-46 (P=0.057>0.050). The skewness value of growth characteristics was between -0.482 to 0.304 and the kurtosis value was mostly between -0.363 to 0.155 in the rest of the pedigrees, close to a normal distribution. The distribution of the height was left skewness distribution, it meant that the number of trees which were greater than the average was more, in contrast, the diameter was right skewness distribution, the number of trees which were greater than the average was less. There were significant differences in height and ground diameter among the pedigrees (P<0.05), but it was not obvious, the average height of 2-2×2-38 was the largest and the smallest one was ZS8×2-7, it was only 7.14% higher. The average diameter of 2-2×2-9 was the largest and the smallest one was ZS8×2-7, it was only 7.52% larger. The growth rhythm of those pedigrees was similar from June to October, it appeared summer dormancy between early July to mid-July possibly. According to the distribution of growth characteristics in those pedigrees, it could carry out the elimination and early selection of superior clones.