Japan–South Korea relations are the diplomatic relations between Japan and South Korea. As the Sea of Japan and the Korea Strait geographically separate the two nations, political interactions date back from the 6th century when the kingdom of Baekje (which encompassed much of present-day South Korea) officially established relations with the Yamato Kingship of Japan. During the ancient era, the southern region of the Korean Peninsula served as the closest port for economic trade and cultural exchange between the Japanese archipelago and mainland Asia. Such relations would continue by the late 19th century when both Japan and Korea underwent modernisation from Western powers up until 1910, when Korea became a colony of Japan.Shortly after gaining independence from the Japanese surrender at the end of World War II in 1945, Korea was divided into two states. During the Korean War, Japan took part in aiding South Korea by providing military supplies to US and UN forces against the communist-led North Korea. Japan and South Korea formally established diplomatic relations in December 1965, under the Treaty on Basic Relations Between Japan and the Republic of Korea, with Japan recognising South Korea as the only legitimate government in the Korean Peninsula. Japan and South Korea share many cultural, economic, and military ties. Their economies are respectively the second and fourth largest in Asia, and they are both military allies of the United States. Relations, however, are complicated by a number of issues, including territorial claims on Liancourt Rocks and conflicting views on mutual history. In spite of the issues, both South Korea and Japan have taken priorities to improve their relationship, and relations between the two countries has improved significantly in the 2020s. Public opinion surveys show that both countries have had an increasingly favorable opinion of each other's countries in the 2020s.
History
Between 1961 and 1979, South Korea's head of state was dictator Park Chung-hee, who had served in the Imperial Japanese military during World War II. Park took a strong interest in Japanese modernization since he witnessed development policies in Manchukuo firsthand. After the war, during a private lunch with Prime Minister Nobusuke Kishi, one of the masterminds behind the pre-war Manchukuo economy, Park compared his own South Korean military clique with "the young people who succeeded with Meiji restoration in Japan." He further added that he and his troops "look up to these people, and try to make our country escape from poverty and build a wealthy and powerful nation." Under Park's government, the two countries pursued the 1965 reconciliation treaty, which brought about normalized relations, despite considerable public opposition. Park was able to force the normalization through the National Assembly and shut down demonstrations through martial law.
As a result, Tokyo provided $300 million as compensation to comfort women, forced laborers and other victims, and extended an additional $200 million credit to Seoul, and Prime Minister Sato attended official functions in July, the first visit of a Japanese premier to postwar Korea. Nevertheless, Seoul objected strongly to occasional visits by Japanese politicians to North Korea, to the continuation of Red Cross repatriation of Korean residents in Japan to North Korea, and to the proposal of Tokyo Governor Minobe to permit a pro-North Korean university in Tokyo. The Japanese Foreign Ministry opposed Minobe on this issue in order to prove its loyalty to South Korea. Meanwhile, contacts between Japan and South Korea increased through new air routes, tourism, and trade.
In 1975, South Korean–Japanese relations improved following the July "settlement" of a two-year-old feud that began when South Korean agents abducted Kim Dae-jung, an opposition leader (and future President of South Korea), from a Tokyo hotel. As a result of the settlement, a long-delayed ministerial conference was held in Seoul in September to discuss economic cooperation between the two countries. Japan joined the United States in providing assurances for South Korea's security. In a joint statement by Japanese Prime Minister Takeo Miki and U.S. President Ford declared: "The security of the Republic of Korea is ... necessary for peace and security in East Asia, including Japan".
Japanese and South Korean relations soured in the early 1990s, following the public coming-out of several former comfort women and the Japanese government's initial denial of any responsibility. This friction soon grew to include disputes concerning Japan's colonization of Korea in general. The Japanese government began to relent somewhat after evidence of "comfort stations" from Japanese state archives was unearthed, leading to the government's preparation of the official Kono statement. In 1996 FIFA announced that the two countries would jointly host the 2002 FIFA World Cup. The next few years would see leaders of both countries meet to warm relations in preparations for the games. Though citizens of both countries were initially unhappy about having to share the honors with the other, and the Liancourt Rocks controversy flared up again, the event turned out to be very successful.
Japanese Prime Ministers in mid-to-late 1990s regularly issued apologies, and relations reached a brief peak in 1998, when President Kim Dae-jung invited Emperor Akihito to possibly visit Korea (something a Japanese emperor had never done before), while Prime Minister Keizō Obuchi offered his "heartfelt apology" for Japanese colonialism during Kim Dae-jung's visit to Japan. This period saw an increase in trade and tourism between the two countries. This brief healing period soured once again in 2001 after revelations of school textbooks approved by the Japanese Ministry of Education which stated that Japanese colonization was necessary for regional security and also removed any mention of comfort women. That same year, Prime Minister Junichiro Koizumi visited Yasukuni Shrine and continued to do so every year during his tenure. Nonetheless, there were some positive overtures, such as Koizumi's visit to South Korean independence landmarks in 2001 and Emperor Akihito reminding the media that he has some Korean ancestry in 2002.
Economic relations The annual trade between Japan and South Korea was $77.2 billion as of 2024. According to an analysis by Bloomberg, the economic links between the two countries, particularly in trade, investment, and finance, are far weaker than would be predicted by the gravity model of trade, especially when compared to the economic links between neighbors in North America and Europe. This lack of economic integration is attributed to their hostile relationship.
According to David Kang and Jiun Bang, South Korea has tried to create a peaceful middle ground with other North Asian countries such as Japan, for business and trade because of its objective to be the "center of Asian business". The two argue that this agreement favors China more than Japan due to South Korea's unsafe political security history with Japan, which has affected the Seoul-Tokyo economic relations. This has led to a decrease in trade and export between both countries; Japanese tourism is one of the big exporting services South Korea offers, which decreased by a rate of approximately 23% between the year 2012 and 2013.
In 2013 South Korea banned the import of fish from eight prefectures in Japan due to growing concerns over the Fukushima nuclear power plant waste incident, after Tokyo Electric Power Company (TEPCO) declared the incident to be a radioactive waste a couple of years after the earthquake. Japan considered the ban a hostile move, leading the Japanese government to file a complaint to the World Trade Organization (WTO) in May 2015, claiming that Seoul was "'discriminating against' Japanese seafood". In October 2017 the WTO issued a ruling, with reports stating that South Korea lost the case. On April 12, 2019, the WTO overturned its previous decision. Nearly 50 countries have enacted bans on Japanese imports following the nuclear disaster of 2011, though Japan has only filed a case to the WTO exclusively on South Korea's import restrictions.
In July 2019, Japan announced that the export of several controlled items to South Korea would now be put through restrictions including a licensing process. Specifically, Japan notified restrictions on fluorinated polyimides, hydrogen fluoride, and photoresists. South Korean tech companies currently import either a majority or a large portion of these three tech imports from Japan. The restrictions came into effect starting on July 4, 2019. In a news release, the Japanese Ministry of Economy, Trade and Industry (METI) gave a lack of trust on their side for South Korea's export control and restriction system, along with the discovery of controlled items being improperly exported by companies to South Korea, as justification of the restrictions. While METI has not given specific details or examples of the above narrative, some media reports claim South Korea may have passed on restricted chemicals to the United Arab Emirates, Iran, or North Korea. South Korea denies claims that their country's export governance is lax, and summoned a Japanese embassy official to speak against Japan's allegations that South Korea was inept in carrying out sanctions against North Korea. South Korean Minister of Trade, Industry and Energy Sung Yun-mo stated that an emergency inspection on companies importing chemicals from Japan came up with no evidence those chemicals were being exported to North Korea, and that Japan's claims were groundless and should be stopped. Others view Japan's trade restrictions as partially being an excuse to retaliate against suspected intellectual property infringement by South Korean companies.
Japan intended to begin a new round of trade restrictions, this time striking South Korea from a list of nations that are viewed as taking necessary measures against the proliferation of conventional weapons and weapons of mass-destruction. A removal from the list enables METI to perform restrictions on any export to South Korea, including those outside the current three key tech-imports, on the basis of national security concerns from Japan's view. In 2021, the South Korean government declared "industrial independence" from Japan, stating that imports of Japanese materials for its industrial sector had been successfully reduced to near zero for key items such as etching gas, photoresist, and fluorinated polyimide. Overall reliance on Japan for the top 100 industrial items had declined to 24.9%, and further efforts were being made to reduce imports of Japanese items. This achievement has been likened by officials to an "independence movement", drawing parallels to the independence struggles during Japan's colonial rule. In March 2023, the dispute over semiconductor materials was resolved ahead of a summit, with South Korea withdrawing its WTO complaint and Japan dropping its export restrictions.
Amidst the 2025–2026 China–Japan diplomatic crisis, after China announced dual-export restrictions on Japan, the Ministry of Trade, Industry and Resources announced South Korea would "preemptively review whether it is possible to replace imported Japanese items subject to China’s export curbs on dual-use goods in order to minimize negative impacts on supply chains".
Concept of a “Korea-Japan Economic Union”
Beginning in 2025, the concept of a “Korea-Japan Economic Union”, advocating that South Korea and Japan should form a fully integrated economic union or economic federation in order to enhance competitiveness, began to be discussed in earnest primarily within business circles.