Abstract: The triple-differences method is a new breakthrough in GPS deformation monitoring system. This paper provides more information about highly accurate GPS deformation system with triple-difference method. The measurement accuracy， measurement technology， measurement data transmission and treatment technology of this deformation monitoring system have been studied through accuracy verification tests and engineering application. The research results show that the GPS deformation measuring technology with triple-difference method is of high measuring precision in terms of the grade of mm， the simplicity， the centralized data processing， the high monitoring efficiency and the function of long-distance data acquisition， receiving and transmission. It is an innovative research achievement in real-time deformation monitoring and is prospective in engineering application in the future.