Abstract: Syzygium album Q. F. Zheng is a key protected wild plant in Fujian Province, with notable shade tolerance potential. However, its physiological responses to varying light conditions remain unclear. This study investigated the seasonal variations in leaf functional traits and chlorophyll fluorescence parameters of four-year-old S. album seedlings under different shading gradients: full light (CK), and light transmittance:100%,75%±5%,50%±5%,25%±5%. The results showed that shading, season, and their interaction had significant effects on leaf functional traits and fluorescence characteristics. Shading significantly increased leaf area of S. album. Shading in spring and summer helps maintain moisture, while in autumn, it is beneficial for dry matter accumulation. In terms of fluorescence response, shading increased the initial fluorescence (F_o), the maximum fluorescence (F_m), and the maximal quantum yield of PSII (F_v/F_m) in spring and winter, stimulating PSII activity and photoprotective responses; in summer and autumn, it regulated the photochemical quenching coefficient (qP) to maintain electron transport activity, enhanced the non-photochemical quenching coefficient (NPQ) and the quantum yield for regulated energy dissipation (Y(NPQ)) for heat dissipation adjustment, and increased the quantum yield for non-regulated energy dissipation (Y(NO)), reflecting seasonal adaptations in energy allocation mechanisms. These findings provide theoretical support for the application of S. album in seedling breeding, species reintroduction and understory greening.