For studying the shielding effectiveness of micron nickel particle in the THz range,this article based on the Mie scattering theory,the theoretical analysis and numerical calculation of the micron nickel particle′s light scattering characteristics in THz range.we obtained the relationship of the optic section with the particle radius and incident wavelength,the scattering intensity with the scattering angle and the size parameter x.The results show that the micron nickel particle′s extinction function is main on scattering in THz band.With the increase of radius,extinction section increased at first and then oscillation reduction,finally tends to a constant value.The scattering intensity is concentrated in a small range of scattering angle and the smaller the radius,the lower the scattering intensity.