The national college students' subject competition is an important means to stimulate students' interest in learning, cultivate their innovative thinking, train their teamwork, improve their comprehensive quality and increase their communication. Urban underground space engineering specialty was first established by Central South University in 2002, which is a relatively new specialty. The corresponding discipline competition of urban underground space engineering specialty has also been held for a short time. At present, only four sessions have been held. Although there are more and more participating colleges and universities with the increase of holding sessions, most universities have not formed a systematic discipline competition construction mode. In order to give full play to the role of discipline competition in talent training and improve the level of undergraduate discipline competition, this paper takes the urban underground space engineering specialty of Xi'an University of Architecture and Technology as an example, analyzes the current situation of the discipline competition, puts forward the establishment of unified management system relying on provincial key laboratory, and proposes the construction ideas of discipline competition. Finally, it discusses the significance of discipline competition on teaching reform and talent training. It's necessary to take this opportunity to improve the level of student participation, enhance the influence of discipline competition, give full play to the significance of discipline competition in talent training, and provide strong support for discipline construction.