In order to solve the problem that the shield cannot receive normally due to size restriction of the receiving end in narrow space, it is necessary to take auxiliary measures to disassemble the main parts and then transport them back to launching shaft along the original shield tunnel and lift them out. A 6 680 mm shield is adopted in the left line between Pinganli Station and Jishuitan Station of Beijing Metro Line 19 Phase Ⅰ Project, through the study on the size and embedded design of the receiving end, the disassembly scheme and sequence in mined space, the auxiliary hoisting technology during the disassembly process, the construction period management and other aspects, the shield disassembly scheme and control points in narrow and mined space are summarized, and the emphasis and difficulties and key technologies of disassembly are analyzed. The results show that the technology ensures the construction safety and progress, solves the technical and safety problems for shield construction in narrow and mined space.