Abstract: In order to calculate the concrete scale range of coal and rock mass in different rockburst danger degrees, and prevent and control rockburst in coal mine,the concept of dynamic system of coal and rock is put forward in this paper. The model of the relationship between the occurrence of rockburst and dynamic system is built at the same time. The calculation method of dynamic system scale and its evaluation system and quantitative indicators are put for-ward based on blasting theory and Mises yield strength criterion. According to the source position and energy value of happened rockburst and microseismic events,the concrete scale range of dynamic nuclear area zone,damage zone,in-jury zone and influence zone are calculated,so that the different rockburst danger degrees in different areas of coal and rock mass could be determined. The accuracy of dynamic system scale calculation method is validated in Laohutai coal mine,and the results show that the calculation method is highly reliable and practical,which could be widely used in forecasting the risk of rockburst.