Abstract: In order to provide reference for the protection and development of Acer catalpifolium, the growth performance of Acer catalpifolium at seedling stage was studied, and the families with good growth traits at the seedling stage were screened. Fifteen half-sib families of Acer catalpifolium were used as the research object, the growth of seedling height and ground diameter traits were analyzed and compared. The results showed that there were significant differences in seedling height and ground diameter of half-sib families of Acer catalpifolium. The family heritability of seedling height and ground diameter was greater than 0.9. There was a significant positive correlation between seedling height and ground diameter. The genetic coefficients of seedling height and ground diameter reached 30.59% and 29.06%, respectively, with great potential for genetic improvement. Two excellent half-sib families were screened.