Abstract: In order to solve the problem of large scale deformation and failure of the underground chamber group in Zhangcun Coal Mine, the stress distribution and deformation characteristics of the group were studied by numerical simulation. The results show that the main contributing factors of deformation and failure are low rock strength and roadway interaction. Because of low rock strength，a plastic zone with a width of 1.5 to 2 times of the roadway is formed around the chamber. Under the influence of roadways, the large scale plastic damage area produced by the connection of plastic zones is the root of deformation and damage of the chamber group in the bottom hole. According to the research conclusions, a roadway repair plan was proposed, and well application effects are achieved in the field through the use of full-length prestress grouting cables.