Abstract: The paper analysed pendulum displacement at arch crown according to the automatic observation data of LN2002A pendulum station on Lijiaxia dam. By statistics analysis method, through multiple stepwise regression analysis, a displacement statistics monitoring model for measuring point on 2 185 m level at arch crown section was built up. The result showed that the fitting resolution of the model is of high accuracy, the factors were clear and the model had actual application value for predicting damdisplacement.