Abstract: This paper presents a detailed comparison of several typical theoretical models describing far-field intensity distributions of laser diode with the experimental results in the literature. It is found that the propagation and far-field properties of laser diode have to be described by the non-paraxial theory, and the far-field intensity distributions vary with the output power in general. Different models should be suitably chosen to simulate the far-field behavior in the fast and slow axes of heterostructure laser diode at different power levels. In addition, the Hermite-Gaussian(H-G) model is modified, where the contributions of the odd-order H-G modes are included and the coherent superposition of H-G modes is replaced by the incoherent superposition of H-G modes. The improved model is