China’s Encroachment In the Yellow Sea Is Making South Korea Nervous: As if tensions aren’t already running high between China and its neighbors, Beijing is provoking yet another crisis. China is building structures in the middle of the Yellow Sea, in a bid to assert sovereignty over waters that are also claimed by South Korea.
South China Sea 2.0 in the Yellow Sea?
Now South Korea may respond in kind by building its own structures in the Yellow Sea. Seoul fears that China will use these structures as springboards to claim control over surrounding waters. China has been accused of using this tactic in the South China Sea to claim Scarborough Shoal from the Philippines. Though Scarborough has not escalated into armed conflict, China’s coast guard has repeatedly harassed a Philippine garrison there.
Located between China to the west, and North and South Korea to the east, the Yellow Sea offers rich fishing grounds at a time when nations are sensitive to food security. It also has oil and gas deposits valuable for energy-hungry China and South Korea.
Despite South Korean protests, China has built three steel structures in the Yellow Sea in 2024, with the latest being spotted by South Korean spy satellites in December. The newest structure is a “mobile steel framework exceeding 50 meters [164 feet] in diameter and height,” according to South Korean media.
China also appears to have emplaced an old oil rig in the Yellow Sea in 2022, South Korean intelligence believes. The rig has been converted into a floating hotel with a helipad as well as accommodations for 70 people.
“China has reportedly described the structures as ‘fishing support facilities,’ dismissing concerns,” South Korea’s Chosun Daily newspaper noted in January 2025. “However, experts warn that continued installations could enable Beijing to assert territorial claims over the area. South Korean officials believe China plans to install up to 12 such structures.”
South Korea is now considering whether to build a “necessary facility” in the Yellow Sea, said Minister of Oceans and Fisheries Kang Do-hyung. “We are strongly protesting to China through diplomatic channels,” Kang said. “We view this matter with utmost seriousness, given its importance and our position on protecting our maritime territory.”
Like many maritime border disputes, the Yellow Sea is complicated. It falls within the exclusive economic zone, or EEZ, of both China and South Korea. Under international law, an EEZ allows nations to claim jurisdiction over economic resources out to 200 miles from their coastlines. EEZs have sparked numerous disputes, including between Turkey and Greece in the Mediterranean, and the notorious “Cod War” between Britain and Iceland in the North Atlantic
South Korea argues that the boundary between the conflicting EEZs should be drawn down the middle of the Yellow Sea. However, “China maintains that the maritime boundary should be proportional to its longer coastline and larger population,” according to the National Bureau of Asian Research, a US think tank.
To calm the dispute, China and South Korea created the Provisional Measures Zone, or PMZ, in 2001. In addition to delineating joint fishing rights and fisheries management, the PMZ also specified that both nations would gradually restrict fishing to their respective EEZs.
Instead, South Korea has long complained about Chinese vessels fishing in Korean waters, which has led to South Korean ships firing on Chinese fishermen.
EEZ disputes are as much about national pride as economics. But the Yellow Sea is particularly sensitive for China. “Most critical battles in Northeast Asia since the 19th century – a period China sees as a brief deviation from its rightful historical trajectory – have been fought in the vicinity of the Yellow Sea,” noted Sang Hun Seok, a former South Korean diplomat.
However, South Korea also has memories of being bullied and exploited by its bigger neighbors China and Japan. In the case of Scarborough Shoal, China has the upper hand because the Philippines is a poor nation with a weak military. But South Korea has the 12th largest economy in the world. And while its military is far smaller than China’s, South Korea has F-35 stealth fighters, ballistic missiles, and submarines. Especially if backed by the United States – which has 29,000 troops in South Korea – Seoul can project considerable power into the Yellow Sea.
What Happens Next?
Both sides have reason to avoid serious conflict. China is focused on Taiwan and potential conflict with the U.S. and its Pacific allies, and its economy is already under stress. South Korea has little incentive for a fight with its much larger neighbor.
Yet economics – and pride – may prevent both nations from backing down.
About the Author: Michael Peck
Michael Peck is a defense writer whose work has appeared in Business Insider, Forbes, Defense News, Foreign Policy magazine, and other publications. He holds an MA in political science from Rutgers Univ. Follow him on Twitter and LinkedIn
