Abstract: Large amount of measured data will produce during the measurement process of light scattering particle size distribution, which could lead error results in terms of coal mine dust measurement. In order to improve the systematic stability and accuracy of coal dust distribution measurement, we try to track and analyze part of the measurement data through Monte Carlo method and distribute weight to establish Monte Carlo data soft measurement model and calculate some key parameters. The results show that the Monte Carlo algorithm can provide a stable and accurate data analysis method in the measurement system of light scattering particle size distribution, which can also provide an effective and reliable method for industrial application.