Through the current domestic and foreign assembly theory and application case studies，it is found that the research and application of fully assembled structure in the light tower structure is rare. Based on the reconstruction project of a container automated terminal in Dalanping，Qinzhou，the structural system of the fully assembled steel light tower is studied. Firstly，the steel structure prefabricated building technology is summarized. Secondly，the selection of light tower structure system is analyzed. Thirdly，the main structural connections of fully assembled structure are studied. Finally，the installation process of fully assembled steel light tower structure is described. Through theoretical research and project application，it is concluded that the fully assembled steel structure light tower has better economic benefit，shortens the construction period，facilitates factory operations，and has good environmental protection effect. It is suitable for projects with tight construction period and high environmental protection requirements，and provides reference for similar projects.