Spherical particle model is often used to evaluate the attenuation of electromagnetic wave by sand and dust storm and retrieval of optical thickness with satellite reflectance sensing. Measurements in laboratory and in situ show that the shapes of natural sand and dust particles are nonspherical,thus suggesting that Mie theory may not be suitable for interpreting the scattering and attenuation properties of sand and dust storm,and it will cause large errors. A model big using shape distributions of polydisperse and randomly oriented spheroid particles was used to model the natural sand and dust particles. The rigorous T-matrix method was used to compute the single scattering of sand and dust storm,and the result was compared with the spherical model. The results show that the phase function averaged over a wide aspect-ratio distribution of spheroids is smooth,featureless and flat at the side-scattering angle and closely resembles those natural sand and dust particles. The multiple scattering characteristics of sand and dust storm were computed by the adding method,and the result indicated that significant errors will be caused with the application of any single shaped particles to compute the scattering characteristics of sand and dust particles.