Abstract: An underground water-sealing oil storage in rock caverns in Liaoning Province follows a low level of ground stress in the low-stress area. After its excavation, surrounding rock deformation and fracture are controlled under the combination between single structure plane and multi-group structure plane. Therefore, it is required to first analyze whether the surrounding rock suffer stress problems or structure plane problems and equivalent to value selection of surrounding rock parameters on the importance. Geological strength index (GSI) proposed by Hoek and Brown are based on rock quality evaluation. It can reduce subjectivity in determining the shear strength indicator to define rock mass mechanics parameters by the empirical formula. The underground water-sealed oil storage in rock caverns in Liaoning Province is taken as the object of study. Using the surrounding rock parameter value selection method based on GSI system as well as FLAC3D software, numerical analysis on the surrounding rock stability is conducted and its results are interpreted based on displacement criteria and stress criterion to determine the surrounding rock stability, thus having a guiding significance in engineering practice.