Abstract: Aiming at the problem of large deformation and serious collapse of the surrounding rock of the roadway under the traditional support scheme of thick-top coal and gangue roof, taking the 818 machine roadway in the 81 mining area of Xinhu Coal Mine as the research object, theoretical analysis and FLAC3D numerical simulation method are used to compare 818 The optimization of the original support parameters of the machine tunnel was carried out, and the composite support technology of "three-center arch U-shaped steel shed + anchor cable beam + lock leg beam" under the thick-top coal gangue roof was proposed, which solved the problem of the thick-top coal gangue in Xinhu Coal Mine. The problem of roadway support under the roof. The results of underground tests and field measurements show that after composite support, the stress state of the surrounding rock of the roadway is significantly improved, and the roof subsidence is controlled near 50mm, which plays a good role in supporting the roadway and can meet the needs of safe and efficient production in the mine.