In December 2007, the Korea Nuclear Safety and Security Commission (NSSC) authorized the lifespan extension of the Gori-1 plant. The decision was a result of the longer historical process, beginning in the early 1990s. This paper divides process into three stages: preparation, policy-making, and local residents’ response. As early as 1993, the Korea Electric Power Corporation actively prepared for the lifespan extension of Gori-1 by conducting a study on plant lifetime management. This was followed by a large-scale facility improvement project in 1998. In December 1999, the NSSC institutionalized periodic safety reviews (PSR), which set the stage for a major preparation for Gori-1’s lifespan extension. Based on the preparatory work, lawmakers at the National Assembly attempted to enact a law on lifespan extension in 2002, which failed without detailed discussions. In September 2005, however, the Korean government managed to revise the Enforcement Decree of Atomic Energy Law, thereby providing the legal foundation for Gori-1’s lifespan extension. The revision was able to slide through without much public scrutiny due to the dominance of the radioactive waste disposal facility issue within Korea society at the time. Within this context, the Korea Hydro & Nuclear Power (KHNP) and the Korea Institute of Nuclear Safety submitted and checked the PSR report, which led to the NSSC authorization in 2007. The opposition movement for the life extension of the Gori-1 plant began with the construction of new nuclear plants and high-pressure transmission lines, and local residents made countermeasure committees for Gori-1’s lifespan extension in late 2006. In June 2007, the opposition movement succeeded in temporarily shutting down Gori-1, which led to a compromise settlement between KHNP and local residents without making it a nationwide issue. In conclusion, the decision to extend the lifespan of Gori-1 proceeded without sufficient public discussions and was cast as a local problem throughout the three stages.