Because of the non-uniformity of raw coal gasification itself , fluctuations are inevitable in the operation of dry powder gasifier, which in turn have a large impact on the indicators of stable gasifier operation. In this paper, based on a dry pulverized gasifier of a plant, the controlled rate and key process parameters affecting the pressurized gasification process stability of pulverized coal are selected to conduct statistical process control analysis of the gasification process of the dry pulverized gasifier, and quantitatively assess the stability of the operation of Shenyou 3 coal in four dry pulverized gasifiers. The study shows that the controlled rate of all parameters is above 95%, and the overall operational stability of the four dry powder gasifiers is good. In order to further improve the stability of gasification operation, it is suggested to adjust the control range of gasifier pressure and effective gas content, improve the analysis and measurement accuracy of pulverized coal flow and methane content, and optimize the structure of gasifier. The statistical process control analysis method can well find some key process parameters fluctuation in gasification process of the dry powder gasifier, thus playing a better guiding role in the production process of the dry powder gasifier.