The installation technology of counterweight system of Three Gorges Project ship lift has been studied in this paper based on the construction requirements of counterweight system and construction environment. The overall installation procedure of counterweight system has been put forward which are suitable for Three Gorges Project. Then the construction processes and construction methods of balance chain guide installation, balancing pulley installation, main hoist rope installation and counterweight installation have been described in detail. At the same time, the installation technology system of counterweight system is set up. This construction technology effectively solves many problems faced in the installation process of counterweight system of Three Gorges Project ship lift, such as large scale project, large component size, high accuracy requirements, high installation elevation, difficult construction, construction with wide distribution, complex construction conditions, etc. Meanwhile, the technology provides a good reference for similar projects at home and abroad.