The direction of thermal radiance is one of the key problems in thermal infrared remote sensing retrieval and product validation. Aiming at row crop, a directional thermal radiance model is built by considering the sunlit/shaded leaf, sunlit/shaded soil, multiple scattering and field of view. The accuracy and sensitivity of the model are discussed and the results show that the model can not only explain the row crop structure and hot spot effect well, but also be suitable for simulating the thermal radiance of continuous canopy. Compared with the FRA97 and the FovMod model, the directional distributions of directional brightness temperature are in good agreement. The root mean square error is 0.18 K and 0.36 K respectively.