In order to explore the effects of shading treatment on photosynthetic characteristics and leaf anatomical structure of Sarcandra glabra, and provide theoretical basis for scientific cultivation of S. glabra, we treated 2yearold S. glabra with four different shading treatments ［L₀ (0%), L₅₀ (50%), L₇₀ (70%), L₉₀ (90%)］ to observe its photosynthesis, leaf anatomical structure and plant growth. The results showed that: (1) with the increase of shading rate, photosynthetic effective radiation(PAR), stomatal conductance(G_s) and transpiration rate(T_r) decreased gradually, intercellular carbon dioxide concentration (C_i) decreased first and then increased, and net photosynthetic rate (P_n) increased first and then decreased; Under L₅₀ and L₇₀ treatments, PAR, G_s, T_r and C_i were lower, photosynthetic ‘midday depression’ was effectively alleviated, and P_n was higher. (2) With the increase of shading rate, the light compensation point (LCP) decreased gradually, the light saturation point (LSP) and dark respiration (R_d) increased first and then decreased, the apparent quantum efficiency (AQE) increased gradually, and the maximum net photosynthetic rate (P_nmax) of leaves increased first and then decreased; Under L₅₀ and L₇₀ treatments, LCP was lower, LSP and AQE were higher, and P_nmax was higher. (3) With the increase of shading rate, the thickness of leaves, epidermal cells, palisade tissue and spongy tissue increased significantly, while the thickness of cuticle became thinner; Under L₅₀ and L₇₀ treatments, palisade tissue and spongy tissue were developed, palisade tissue cell length became shorter, spongy tissue thickness increased significantly, cell arrangement was loose, and chloroplast number increased significantly; Mesophyll cell and chloroplast structure were complete, granal thylakoid and stromal thylakoid lamellar structure were developed, and the ability of leaf to capture light was enhanced. (4) With the increase of shading rate, the plant height, ground diameter, total leaf area and biomass of S. glabra increased first and then decreased. Under L₇₀ treatment, the plant height, ground diameter, total leaf area and biomass reached the peak values of 58.58 cm, 5.09 mm, 1 038.53 cm² and 15.50 g, respectively. Conclusion: S. glabra has a certain weak light tolerance and light plasticity. 50%～70% shading treatment is beneficial to the growth of S. glabra. In actual production, suitable intercropping stand or shading treatment can be selected according to the light range.