The activities of the Truth and Reconciliation Commission, Republic of Korea which has aimed at revealing the truth of the past tragic accidents ended at June, 2010. The Commission revealed the truth of the mass murder of the subscribers to the National Guidance Alliance just after the outbreak of the Korean War. Also the mass killings at Hampyong, Namwon and Kochang, which were done by the 11th Division, were included in activities of the Commission. Now Researchers have to advance their studies on the basis of the revelations of the civilian massacre. Above all, they have to clarify the number of the murdered at the case of the National Guidance Alliance, on the basis of the Truth and Reconciliation Commission, Republic of Korea. The case is believed to turn out the most dead persons. The study of the civilian massacre must bring the focus on the problem of assailants. The study has to be focused on the illegal killing of civilians by the assailants and the psychological and the social situations of the killers. The role of President Syngman Rhee and his government at the large-scale civilian massacre also has to be clarified. The investigation of the responsibility of the U.S. government and the U.S. Armed Forces at the massacre is also necessary. The investigators have to make clear how to the large-scale civilian massacre acted on the maintenance of the extreme anti-communist regime.