Dam deformation monitoring is a very important work in dam operation and management，and whether the benchmark control point is stable is the premise of accurate dam deformation monitoring.Based on the analysis of the re measured values of the control network of Shankouyan water control project in Pingxiang city，this paper introduces the layout requirements of the horizontal control network and the matters needing attention in field observation，and analyzes the stability of the reference control points.Compared with the first measured value，the fixed angle and fixed edge of the measurement control point meet the specification requirements.The stability of the benchmark control points can improve the observation accuracy of the dam deformation monitoring points and accurately predict the safe operation of the dam.