Vegetation plays an important role in the earth’s ecosystem, and it has always been a focus of quantitative remote sensing research. The spatial heterogeneity of the vegetation canopy results in the complicated Bidirectional Reflectance Factor (BRF) distribution which brings great difficulties to the high-resolution vegetation remote sensing research. The 3D radiation transmission model can accurately describes the interaction between heterogeneous vegetation canopy and solar radiation, which is important for modeling and application of vegetation quantitative remote sensing using high-resolution optical data.In this work, the probabilistic plants with statistical properties similar to actual plants are used to construct a 3D vegetation canopy. Combining Monte Carlo ray tracing technology and canopy porosity calculation, a 3D canopy radiation transmission model is constructed by rationally designing the random transmission process of optical particles in the canopy. Using probabilistic plants to build the canopy not only accurately describes the canopy’s heterogeneity but also takes into account the non-uniform spatial distribution of leaves. The model considers light to be a particle with the dual properties of frequency and energy. The Monte Carlo method is used to simulate the transmission behavior of light particles in the canopy, and the canopy porosity is calculated to improve the model’s calculation stability.Taking the corn canopy with a typical ridge planting structure as an example, the bidirectional reflectance function of the corn canopy in different growth periods is simulated and compared with the multi-angle observation data. The comparison results illustrate that the model has good simulation accuracy for the optical BRF of corn canopy in different growing periods. The RMSE between the model simulation value and the measured value is 0.0085 at the red band, and the R² is 0.96. At the near-infrared band, the RMSE and R² are 0.013 and 0.96, respectively. For the homogeneous canopy, the comparison between the model developed in this work and the SAIL model shows that the model of this paper perfectly describes the transport path and energy transfer of the light particles.The model proposed in this paper can accurately simulate the BRF of the canopy with the centrosymmetric statistical characteristics, and it offers great convenience in constructing inhomogeneous canopy scenes as well as high simulation stability. The model provides an effective simulation tool for studying canopy BRF and supporting verification of key canopy parameters such as vegetation biomass and leaf area index.

probability plants;three-dimensional canopy;Monte Carlo;canopy porosity;bidirectional reflectance function