One of the methods that can be used to investigate the damage area caused by excavation of underground spaces is the acoustic propagation method. This method is based on receiving elastic waves produced due to deformation and cracking in the rock mass surrounding the space under stress. In this research, the damage area caused by excavation of a horseshoe tunnel has been studied using laboratory tests assisted by an acoustic propagation device, numerical and statistical methods. In order to study the damage area around the tunnel, a uniaxial compression test was performed on cores obtained from drilling a borehole in the wall of a tunnel, along with acoustic recordings. A numerical model of the tunnel was built in FLAC^3D software and run under the conditions of the tests. In the next step, the relationship between the damage areas obtained from the laboratory sample and the yield areas obtained from the numerical model was compared by FLAC^3D software. Mathematical relations for estimating the damage area caused by excavation under non-uniform stress conditions were obtained based on the results of numerical modeling by SPSS software. These mathematical relationships are based on the adhesion, internal friction angle, and tensile strength of the rock mass around the tunnel, the amount of vertical stress, the ratio of horizontal to vertical stress, and the ratio of resistance to stress.