Abstract: This article takes the installation of the main transformer of Silin Power Station as an example, summarizes the construction methods, process requirements, quality control points, precautions and field tests of the key procedures in the installation and test of large-scale transformers in hydropower stations; focuses on the optimization and improvement of the main transformer installation plan , Which not only guarantees the overall quality of the installation of the four large transformers, but also speeds up the construction progress, ensuring the smooth realization of the power generation target of the “four operations in a year” of the hydropower station.