Abstract: China is still at the beginning stages of underground oil storage,and thus it is not deep enough. It is essential for us to study and absorb the advanced experience and technology of the foreign countries. In this field, which has so far gained little attention in China, the geological conditions of the rock mass are the key factors to the successful oil storage. The authors, therefore, compare and analyze the geological conditions of the oil storage bases in some foreign countries, and put forward the geological factors that should be considered in underground oil storage.