Abstract：We collect and sort observation data of water pipe inclination at Yunxian station and filter out the fixed frequency component of solid tide. We then eliminate the rain interference, construct a linear equation of monthly precipitation and monthly tilt increment, thus obtaining the residual error between the actual measured value and the theoretical value. The results show that the starting or ending time of the two-component anomalous change in the tilt observation is of certain significance to the time of future earthquakes, within 500 km around the station. In particular, when the residual quantity is greater than 1 times, the mean residual quantity anomaly starts within one to six months, earthquakes of magnitude 5 or more will occur within the range of 200 km from the station, and earthquakes of magnitude 6 or more will occur within the range of 500 km from the station. The results of the forecast efficiency test show that the method has good earthquake reflection effect on earthquakes of magnitude 5 or more in Yunnan region, and can provide a quantitative criterion for the analysis of medium-short impending earthquake trends in this area.