Wildfire is an important disturbance factor of the boreal forest ecosystem of China. With global warming,wildfire disturbance is much more serious. In this paper,the dynamic changes of soil microbial biomass carbon and nitrogen were measured at three different restoration stages of Dahurian larch(Larix gmelinii) forests after severe fire disturbance in the Daxing'an Mountains. The results indicated that the soil microbial biomass carbon and nitrogen increased at the beginning of the growing season and then decreased until the end of the growing season,and the microbial biomass carbon and nitrogen were higher in upper layer soil than in lower layer soil. The soil microbial biomass nitrogen in the plots 3 and 28 years after fire disturbance was higher than that in control plots,and vice versa in plots 9 years after fire disturbance. The soil microbial biomass carbon in plots 3 years after fire disturbance was lower than that in control plots,and vice versa in plots 9 and 28 years after fire disturbance. The soil microbial biomass carbon and nitrogen reached the maximum value in June and then decreased until the end of the growing season. There was a significant negative correlation between the soil microbial biomass carbon and phosphorus in upper layer in plots 9 years after fire disturbance. The soil microbial biomass nitrogen was negatively correlated with the soil water content in lower layer in plots 9 years after fire disturbance. The results of this study will provide a reference for assessing soil microbial biomass nitrogen and carbon and its impact factors after fire disturbance in boreal forest of China.