Abstract: Aiming at the difficulty of the traditional monitoring methods for internal settlement of rock-fill dams to meet the technical requirements for monitoring the internal settlement of high rock-fill dams and the deficiencies in the existing monitoring methods, a method is proposed for measuring the internal settlement of high rock-fill dams based on the pipeline measuring robot. Firstly, the principle for measuring the internal settlement of the high rockfill dams based on the pipeline measuring robot and the composition and deployment method of the monitoring system are introduced. Then, the accuracy of the elevation measurement of the pipeline robot is verified through the model tests, and finally, it is successfully applied to Lianghekou Dam. The elevation check results show that the accuracy of the elevation measurement using the pipeline measuring robot has reached 0.32 mm. A period of pipeline settlement monitoring data with the same starting and ending time as the hydraulic overflow settlement gauge is selected for comparison. Among them, the repeated accuracy of pipeline elevation measurement of the starting and ending time reaches 15 ppm and 10 ppm, respectively. The comparison shows that the monitoring results of the two monitoring systems are in agreement, and they are strongly correlated. Engineering applications show that the measureing method for the internal settlement of high rockfill dams based on the pipeline measuring robot can be effectively used to monitor the internal settlement of rockfill dams, and it is a new type of deformation monitoring technology with good application prospects.