The urban shallow large-section underground structure has become important and difficult part of engineering because of the complexity of its structure and construction.How to apply monitoring technology to supervise the stress transition of surrounding rock,supporting and intermediate structures has become the critical step of the construction.The paper took the example of Dongzhimen Station project in Beijing Urban Rail Transportation,discussed and analyzed the monitoring technology and method in the deep excavation construction of shallow flat group cavities.Comparative analysis was made on monitoring results to verify the rationality of the construction method.