Abstract In order to reflect the internal law of dam deformation data more accurately, the stability and safety of the dam are evaluated and effective measures are taken in time. The Lixi dam in Guangzhou was selected as the research object. 753 sets of data of 4 # hydrostatic level from September 2015 to March 2019 were collected, 355 sets of data from September 2015 to December 2017 were selected as the training set to establish the model, and 328 sets of data from January 2018 to December 2018 were used as the model verification set to evaluate the performance of the model,From January 2019 to March 2019, 70 sets of data were used as model test sets. Stepwise regression analysis model and time series model were used to model and verify the analysis.The forecasting results of sample test set show that the mean square error of stepwise regression analysis model test set is 0.022 and the determinant coefficient is 0.951; the mean square error of time series model test set is 0.007 and the determinant coefficient is 0.985. The results show that the time series model is better than the stepwise regression model in fitting, forecasting and error analysis.