It is necessary to optimize operable factors in measurement of pulverized coal flow by Laser-induced Breakdown Spectroscopy(LIBS). Therefore, this paper investigated the effects of three main operable factors, irradiance, integration delay time and the rate of flow per unit area on the measurement of pulverized coal flow by LIBS based on orthogonal experiments. Pulverized coal was chosen for the experimental sample and the statistic analysis and variance analysis were performed. Experiment indicates that the irradiance and integration delay time are two remarkable factors for the effective excitation rate and the following is the rate of flow per unit area. The optimum parameters of control from the experiment are the irradiance of 9.4×1011 W/cm2 , the integration delay time of 1 500 ns, and the rate of flow is selected reasonably based on economy principles. The results obtained demonstrate that the method can direct the practical measurement of pulverized coal flows in real time.