Abstract: In the paper, all the horiznotal deformation data from Nankou and Dahuichang areas are analysed and the results show that the tectonic movement of the areas was stronger during 1988-1989 and that although the change of the trend of the movement was less, the rate was obviously lowre from 1989 to 1991. This process of the movement is possibly related to Datong earthquake (1989). The movement of the fault blocks in the areas mainly showed the movement property of detachment and spread.