Abstract: It is challenging to simulate the appearance of plant leaves due to complex internal structures and optical properties of leaves.In order to solve this problem, a leaf appearance model with some physiological parameters is proposed in this paper.This model uses a single N-layer plate to construct leaves of single cotyledons plants and two N-layer plates for leaves of double cotyledons plants.In the proposed model, the diffuse reflectance and transmittance are depicted by a leaf scattering models for remote sensing applications called PROSPECT and the glossy term is described by the Cook-Torrance model.The proposed leaf appearance model is formulated into a parametric model with BRDF+BTDF forms.Additionally, a leaf aging algorithm is proposed to extend our model to a time-spatial variant model.The experimental results demonstrate that the proposed model is capable of generating different appearance of plant leaves by controlling certain physiology parameters, such as the chlorophyll content, carotene content and blade internal structure.Moreover, the spatial variant color distribution and time-varying color aging can also be easily simulated, with pleasant realistic effects and fast rendering speed.This satisfies various requirements from real-time interaction applications.