Abstract: The effects of planting density on the early growth, soil physicochemical properties and enzyme activity of Phoebe zhennan plantation were explored, which provided theoretical basis for maintaining soil fertility and sustainable management of P. zhennan plantation. The 6-year-old P. zhennan plantation with three different planting densities (D1: 667 trees/hm², D2: 833 trees/hm², and D3: 1111 trees/hm²) was selected as the research object. The growth characteristics such as tree height and diameter at breast height were investigated, and soil physicochemical properties and enzyme activity in different soil layers (0-10 cm, 10-20 cm, and 20-30 cm) were measured. The early response of tree growth, soil physicochemical properties, and enzyme activity to planting density in P. zhennan plantation were analyzed. The results showed that with the increase of planting density, the average DBH, wood volume, and crown projection area of P. zhennan plantation decreased gradually. The D1 density stand was significantly higher than that of D2 and D3 stands, indicating that relatively low planting density was more conducive to the accumulation of wood volume in P. zhennan plantation. Planting density had a significant effect on soil nitrate nitrogen (P˂0.01), and planting density and soil depth had significant effects on soil pH and total nitrogen (P˂0.01). Soil of P. zhennan plantation was weakly alkaline. In the same soil layer, with the increase of stand density, soil pH and moisture content decreased, while soil organic carbon content gradually increased. With the increase of soil depth, soil total nitrogen, nitrate nitrogen, ammonium nitrogen, and total phosphorus content gradually decreased, indicating a significant "surface aggregation" phenomenon in the soil of P. zhennan plantation. In the same soil layer, the urease and sucrase activities of P. zhennan plantation with D1 density were the strongest, and the sucrase activities decreased with the increase of planting density. Comprehensive analysis of density effects on tree growth and soil quality showed that the comprehensive indexes of tree growth and soil quality in D1 and D2 density stands were the largest, reaching 0.61 and 0.56 respectively, indicating that relatively low stand density played a certain role in improving tree growth and soil quality. Therefore, it is recommended that the reserved density of 6-year-old P. zhennan plantation should not be higher than 833 trees/hm², which is more conducive to improving soil quality and promoting tree growth.