The nuclear power plant water diversion tunnel is adjacent to conventional island and pump room structure, and the construction site is limited. As a result, the shield can not be integrally launched. The separated launching of shield is realized by rehabilitation of pipeline of shield trolley, mucking belt and battery car marshalling. The success of application of separated launching of shield to nuclear power plant water diversion project shows that the abovementioned technology is feasible for limited space and is worth popularizing.