This paper presents bistatic scattering response of rice canopy over growth stages based on a three-layer microwave scattering model, which is developed using the iterative solution of the vector radiative transfer equations up to the second order, and the dense medium phase and amplitude correction theory (DM-PACT) is used to improve the phase matrix taking coherent effects into account. To validate the model, ground-based measurements of backscattering coefficients over an entire rice-growth stage is used. Then, the bistatic scattering response of rice canopy is analyzed in respect of canopy components, including plant height, structure, soil moisture, and surface roughness, as well as their interactions with sensor configurations, such as frequency, polarization, and incident angle. The sensitivity analysis was carried out to demonstrate how the model reacts to changes of each input. The results show that bistatic scattering coefficient varies greatly over different stages, and is strongly dependent on rice plants' structure, including the size, shape, and orientation, especially stems.