Abstract: The main body of Shandong section of the first phase of the East Route of South to North Water Diversion Project has been completed.The surveying control network laid out in the construction period was of a low level, and the measurement datum point was seriously damaged during the construction process.In order to meet the safety monitoring requirements of channels and main buildings in the initial stage of the project, a unified deformation monitoring network for the whole route has been set up in Shandong Province of the first phase of the East Route of South to North Water Diversion Project.Taking the southern Shandong section of the monitoring network as an example, GNSS method and high Leveling Surveying method are used to obtain data, and the observation scheme, technical indices, data processing and adjustment accuracy analysis of the construction of deformation monitoring network are systematically discussed.The results show that the construction of high-level and high-precision deformation monitoring network provides a unified control benchmark for engineering operation management and deformation monitoring, and the construction of deformation monitoring network by GNSS method shows great advantages in terms of operation accuracy, work efficiency, monitoring continuity, real-time and less external interference.The measurement technology of deformation monitoring network in Shandong section of the first phase of East Route of South to North Water Diversion Project can provide reference for deformation monitoring projects of similar large-scale water diversion projects.