This study compares and analyzes the background, performance, and limitations of the 1st to 5th inter-Korean summit. In addition, the contents of the Joint Declaration of the North and the South will be comparatively analyzed and the future summit will be forecast. The five inter-Korean summits expressed strong willingness for the unification of the leaders, and the Kim Dae-jung administration's sunshine policy was succeeded and developed. The hosting of the inter-Korean summit were mainly due to the North Korean economic crisis and active reconciliation efforts between the two Koreas. Through the inter-Korean summit, an atmosphere of reconciliation and cooperation between the two Koreas and an agreement on the joint declaration of the two Koreas were drawn up, but the agreed issues were not continuously implemented according to the North Korean military threat (nuclear threat) and the South Korean government's policy toward North Korea. However, the <6·15 Joint Declaration>, <10·4 Joint Declaration>, <Panmunjeom Declaration>, and <Pyongyang Joint Declaration>, which were jointly declared at the North-South Summit, have similarities to the results that led to the development of sustainable inter-Korean relations. In particular, while the June 15 Joint Declaration was quite comprehensive, declarative, and normative, there has been a difference that the October 4 Joint Declaration, the Panmunjom Declaration, and the Pyongyang Joint Declaration consisted of concrete and practical provisions for the inter-Korean issue. The implementation of these summits and the Joint Declaration will bring positive effects to inter-Korean peace, inter-Korean development and regional development. Therefore, in order to promote the 6th inter-Korean summit and the North American summit in the future, five tasks are proposed.