For the purpose of studying the attenuation characteristics of terahertz wave in dust atmosphere, using the Mie scattering theory, the influence of the dimension parameters of particles on the scattering efficiency factor was simulated, and the value of scattering phase function under different scattering angles, in the condition of single scattering were calcutated. Besides, the relationship between the attenuation of terahertz wave per unit distance in dust particles with certain size distribution and the visibility was simulated. In addition, the multiple scattering of terahertz wave in sand-dust condition was simulated, using Monte Carlo method. And the energy losses of terahertz wave in different visibilities and different dust types were discussed. The results show that the attenuation of terahertz wave is mainly determined by the dimension parameter, in the condition of single attenuation; and the multiple scattering must be taken into account when visibility is low. The results provide a reference point for the application of terahertz wave in those areas such as environmental monitoring, soot and wind-blown sand detection.