Abstract: In order to explore the optimal light conditions for the growth and development of Keteleeria fortunei var. cyclolepis seedlings. 1.5-year-old K. fortunei var. cyclolepis seedlings were treated with different light intensities (full light , shading rate 40%,60%, and 80%) for 2 years，and their morphological growth, chlorophyll content, chlorophyll fluorescence parameters, biomass accumulation and distribution were analyzed. The results showed that: (1) With the increase of shading, the growth of ground diameter and the thickness of leaves decreased, the growth of plant height , the leaf area and specific leaf area increased, the dry weight of the leaves increased first and then decreased;(2) The chlorophyll content, the initial fluorescence (Fo), the potential activity of PSII(Fv/Fo), the maximum photochemical quantum yield of PSII(Fv/Fm), the actual photochemical quantum yield of PSII Y (II), and the electron transfer rate ETR of leaves were all increased due to shading;(3) The leaf, stem, root biomass and total biomass of seedlings under shading treatment showed a trend of decreasing with the decrease of light intensity. The root biomass ratio and root shoot ratio of seedlings decreased, while the leaf biomass ratio, stem biomass ratio and photosynthetic and non photosynthetic tissue biomass ratio increased. The study found that the growth and development of K. fortunei var. cyclolepis seedlings were inhibited under full light, and shading could significantly affect their growth and chlorophyll fluorescence characteristics. The K. fortunei var. cyclolepis seedlings were less stressed under 60% shading rate, and their growth, leaf characteristics, photosynthetic capacity, biomass accumulation and distribution were the best.