Abstract: Based on the bidirectional reflectance model of multicomponent vegetation canopies and the radiative transfer theory, the bidirectional reflectance model of multicomponent rice canopies was developed considering the features of rice cluster architecture and the different characteristics of rice in its different growth period. The comparison between the calculated and measured values show that the model can basically simulate the angular distribution characteristics of reflectance spectrum of rice canopies. The hotspot effect of rice canopies reached the peak at about 37°, which was the average inclination angle of all components belonging to rice, and then the hotspot effect decreased with the increasing average inclination angle of these components of rice. The results of sensitivity analysis proved that the model is feasible in mathmatics.