Abstract: The geologic environment and monitoring system of Baishuihe landslide are introduced.The deformation of the landslide is regarded as the function of the time and the groundwater level,and Taylor series is used to erect the functional relationship of the deformation to the time and the groundwater level,the remainder term of Taylor series and the variation of coefficients of second power of the variation of the time and second power of the variation of the groundwater level are regarded as dynamic noises whose mathematical expectation are 0 to erect Kalman filter model and predict the deformation of the landslide.An example of calculation shows that the fitted effect and the forecast effect of the model are better.