Two tests of Pinus elliottii var. elliottii × P. caribaea var. hondurensis hybrids (EH hybrids) which were planted in Hongling Seed Orchard, Taishan, Guangdong Province were used for measuring growth traits at the ages from 2 to 21a. The genetic effect, juvenile-mature correlation, and the best age of early selection on tree height, DBH, and individual volume were analyzed. The results were as follows: ① Parental effect, maternal effect, and parental interaction effect all had a certain impact on tree height, DBH and individual volume growth of hybrid progeny. To obtain excellent progenies, it was necessary to breed good crossing parents and carried out a wide range of mating and testing. ② The range of individual narrow-sense heritabilities and family mean heritabilities for tree height, DBH and individual volume at different ages were 0.157-0.762 and 0.609-0.920, respectively. These indicated that it was effective to carry out family selection and individual selection in EH hybrids. ③ There was a significant correlation between the early tree height, early DBH, early individual volume and individual volume at 21a or 18 a, which showed that the early selection of growth traits is feasible. Under the premise of considering the unit time benefit, the best ages of individual selection and family selection were 5-6 a and 3-4 a, respectively. ④ Since the survival rates of experimental stands in middle and late stages were usually low, this study provided a discussion about the appropriate evaluation ages of genetic test.