This article examines the complex dynamics of Japan–South Korea relations during the pivotal decade of 1970-1980. It analyzes the significant shifts in bilateral ties, influenced by changing domestic politics, regional security concerns, and economic developments in both countries. The research begins by exploring the historical context, including the lingering effects of Japan's colonial rule and the impact of the Korean War. It then delves into the 1965 normalization of diplomatic relations, setting the stage for the decade under study. The paper investigates key events and trends that shaped bilateral relations during this period. These include the impact of President Park Chung-hee's Yushin Constitution in South Korea, Japan's "Fukuda Doctrine" in foreign policy, and the assassination of Park in 1979. The study also analyzes the role of the United States in mediating and influencing Japan–South Korea relations within the context of Cold War dynamics. Economic aspects are closely examined, focusing on Japan's economic assistance to South Korea and the growing trade relations between the two countries. The research also explores cultural exchanges and people-to-people contacts that emerged during this period. Furthermore, the study addresses ongoing historical disputes, such as the comfort women issue and territorial claims over Dokdo/Takeshima, analyzing how these affected bilateral relations. The paper concludes by assessing the overall trajectory of Japan–South Korea relations during the 1970s, identifying patterns of cooperation and conflict that would continue to influence their relationship in subsequent decades.

Keywords: Bilateral diplomacy, Post-colonial relations, Economic cooperation, Cold War politics, Historical reconciliation.