Abstract: It is prospective to use underground rock cave as storage for oil and gas. Huangdao underground storage is the only oil and gas storage with a capacity of over 10⁵ m³ in China. There are a lot of problems to be solved in cave construction, because the underground storage is a perpetual and hard to maintain. The most important, complicate and perilous problem is the installation of the underground submersing pump and clearance pump. This paper describes the storage principle of underground grotto and the construction characteristics of submersing pump and clearance pump, and describes the installation of the underground submersing pump in details. It is considered that the operation of the underground storage can offer an effective way for domestic oil storage.