Abstract: 3 000 leaf-use Cyclocarya paliurus seedlings (1-year) were planted with six densities (30 cm×30 cm, 50 cm×50 cm, 80 cm×80 cm, 100 cm×100 cm, 150 cm×150 cm and 200 cm×200 cm) for experiment. In May and September 2017, May and November 2018 and October 2019, determinations were carried out on growth traits of seedling and in October 2019, on single seedling biomass and stand unit area leaf biomass. The results showed that height growth of seedlings with high density was larger than that with lower one 1-2 year later, but it became opposite 3 years later. Ground diameter of seedlings with density of 100 cm×100 cm was the largest. Canopy of seedlings increased with the increase of density, but the range from 100 cm×100 cm to 200 cm×200 cm was not significant. Seedlings with density of 100 cm×100 cm had the biggest single plant leaf biomass, the experiment showed that the smaller the density, the smaller the single plat leaf biomass, the larger the per unit area biomass.