Abstract: On analysing the present situation of exploiting the underground space in Beijing and its deverloping trend, this paper divides the underground space into different layers from the angle of construction technology. It discusses the technical characteristics of the exploiting projects. It also deals with the main technical problems which would be met in the constructions for the near future. Then, it inquires into the technical plan made for the earth retaining structure in deep excavation. Finally,the paper introduces briefly the present situation of the international devioping tendency of construction technology in exploiting deep and ultradepth underground space.