In the construction of underground opening by the mountain tunnel method, the stability of tunnel face cannot be ensured depending on rock mass conditions, and a collapse phenomenon may occur. For this reason, many studies have been carried out about the stability of tunnel face. However, most of previous studies have been performed without considering the spatial heterogeneity of geomechanical properties. In this study, in order to collect effects of spatial heterogeneity of geomechanical properties on the stability of tunnel face, basic stability analyses of tunnel face considering the spatial heterogeneity of geomechanical properties in soft rock mass were carried out based on the random field theory. It was clear that the effect on displacement and maximum shear strain on tunnel face was large depending on heterogeneous condition in rock mass, and it was necessary to properly evaluate the effect.