This study involved the simulation of the excavation of the main level of the underground Kittilä mine in Kittilä, Finland. Due to stability issues such as shotcrete failure and rock fallout encountered previously in the mine in underground conditions, rock mechanics analysis has been performed earlier for other mine locations and geometry. This study was focused on the 3-dimensional rock mechanics stability analysis of the excavations of the main level, situated at a depth of 900 m from the surface. The study was performed primarily with 3DEC, using the relevant intact rock strength data, the interpreted rock quality as obtained from core logging and tunnel mapping, the interpreted fault zones and fracturing as well as the interpreted in situ stress state. Simulations included excavation staging along with the planned reinforcements while considering the effect of the stopes.