Abstract: In view of process of measuring 0.1 m~10 m particles with laser scattering method, the parameters-analysis, calculation and optimization of its selection on Mie scattering theory are complicated and cumbersome. Through the comparison on convergence speed, refractive index, scale parameter measurement range and superposition times, we adopted an improved algorithm of Mie scattering parameter based on MATLAB. By combining with MATLAB-s strong computing power and LabVIEW-s graphical interface we did the mixed programming of LabVIEW and MATLAB, and designed a parametric analysis system on theory of Mie scattering which mainly calculated and analyzed the scattering coefficient, the relationship curve between scattering coefficient and particles diameter, the distribution curve of scattering intensity, the effect of incident light-s wavelength, particle-s diameter and polarization angle of incident light on the scattering intensity. The comparison between experimental results and conclusions shows that the system is feasible and the reckoning of scattering coefficient, extinction coefficient and the scattering intensity can be accurate to 17 decimal places, thus it achieves the purpose of reducing a large number of computation and programming work.