Abstract: In the period of 1966-1976, the strong earthquake occurred repeatedly in North China. In this paper, after making the comparison between the Xingtai swarm first occurred and the Datong earthquake, it is found that they are same in many aspects. Then the characteristics of the grouped strong earthquake activity in North China have been analyzed for Shanxi Province. The result shows that the probability of occurrence of strong earthquakes in shanxi province grouped with the Datong earthquake in recent years is relatively high.