The mines expand slowly into deeper deposits through underground mining, and it is related to geotechnical challenges concerned with unexpected failure. The radius of the failure zone and the extent of rock mass deformation in the precinct of opening can be restrained by the implementation of internal support pressure. It is essential to primarily understand the time-dependent behavior of the rock mass. This study aimed to estimate the support pressure of underground gold mine in weak rock mass zone in Indonesia and evaluate the time-dependent support pressure. Rock mass quality Q-system is used as the basis for analysis in this study. To understand the time-dependent behaviour of the rock mass, the support pressure related to the short-term rock mass quality were evaluated. In this study of opening excavated in the weak rock mass, support pressure may progressively increase with time attributable to the creep behavior of the rock mass. The time-dependent behavior of rock mass is indispensable to be contemplated in the long-term design and continuance of underground excavation.