Abstract: The underground gas storage plays an important role in adjusting contradiction of supply and demand of natural gas inwinter and summer, ensuring the requirement of consumers and optimizing the function of gathering and transferring system.Theconstruction of such an underground gas storage abroad has hundred of years history,but it is just in initial phase in China.Along with the implementations of north Shaanxi's natural gas transferred toward Beijing and the Blue Sky project in Beijing, theguarantee of the use of natural gas of Beijing has become the premier issue of natural gas supplier. On the basis of explanationof concept and theory of undergroun gas storage, the chief conditions as necessary for construction of the underground gas storageare provided. Through the analysis of investigation results of concerned stuffs or data at home and abroad, the geology-selectedrules for construction of underground gas storage have been summed up. At the same time, taking the construction project ofunderground gas storage of the condensate gas reservoir in Dagang oilfield as example, the design gist, theory and running projectoptimization are presented.

Key words: underground gas storage, concept, selection, project