[Objective] To investigate the effects of different shading levels on the photosynthetic characteristics and leaf anatomical structure of wild plant Ranunculus ternatus Thunb and provide a theoretical basis for in-depth understanding of its negative tolerance and large-scale planting[Methods] This experiment adopts the method of controlling variables and Ranunculus ternatus Thunb was used as experimental material. Five shading treatments (CK),30% shading (T1),50% shading (T2),70% shading (T3) and 90% shading (T4) were applied.[Results]（1）With the increase of shading, the leaf area reached the maximum under T3 environment; Plant height and stem diameter decreased with the decrease of light.（2）With the increase of shading, the leaf apparent quantum efficiency (AQE) of Ranunculus ternatus first increased and then decreased, and was significantly lower than other treatments under T4 treatment; Light Saturation Point (LSP),light compensation point (LCP),dark respiration rate (Rd) and maximum net photosynthetic rate (Pnmax) decreased gradually;Maximum fluorescence (Fm), variable fluorescence (Fv), maximized chemical efficiency (Fv/Fm) and PSII potential activity (Fv/F0) increased first and then decreased, while the electron ratio (φDo) of the initial fluorescence (F0) heat dissipation decreased first and then increased.（3）With the increase of shading, the stomatal density of Ranunculus ternatus first decreased and then increased, and reached the minimum value at T3 treatment. the thickness of the upper and lower epidermis and the thickness of the sponge gradually decreased, the tissue structure compactness (CTR) decreased first and then increased, and the tissue structure porosity (SR) first increased and then decreased.（4）Leaf palisade tissue, sponge tissue, leaf thickness, and upper and lower epidermal thickness were significantly or positively correlated with Rd. Sponge tissue thickness(ST) 、CTR and SR were significantly positively correlated with Pnmax; (P/S) and SR were significantly positively correlated with AQE .However,sponge tissue thickness(ST) and SR were significantly negatively correlated with F0 .[Conclusion]Ranunculus ternatus can improve its negative tolerance by reducing the photosynthetic rate and changing the leaf structure, it grows well in full light and can also adapt well to 30%-70% shading environment.