Key facts
- South Korean stocks opened lower on Monday, June 29, 2026.
- The KOSPI index fell 2.11 percent to 8,244.67.
- Investor caution stems from renewed uncertainty over the U.S.-Iran ceasefire and rising oil prices.
- U.S. stock markets also experienced declines on the preceding Friday.
- Major South Korean chipmakers Samsung Electronics and SK hynix are expected to announce significant investment plans.
- The Korean won weakened against the U.S. dollar.
Seoul shares opened lower on Monday, June 29, 2026, as investor sentiment was cautious amid renewed uncertainty over the fragile U.S.-Iran ceasefire and rising oil prices. The benchmark Korea Composite Stock Price Index (KOSPI) fell 2.11 percent to 8,244.67 as of 9:15 a.m.
Oil prices climbed after the U.S. and Iran exchanged fresh strikes over the weekend, raising concerns about energy supplies and shipping traffic through the Strait of Hormuz. Reports indicated the two sides agreed to halt recent hostilities and renew talks.
On the preceding Friday, U.S. stock markets saw declines, with the S&P 500 slipping 0.05 percent, the Nasdaq composite declining 0.24 percent, and the Dow Jones Industrial Average falling 0.09 percent.
Investors were also observing a cautious stance ahead of major long-term investment plans to be unveiled by South Korea's top two chipmakers, Samsung Electronics and SK hynix, at a meeting chaired by President Lee Jae Myung. These plans include large-scale infrastructure investments to expand the country's semiconductor production capacity.
Market bellwether Samsung Electronics saw its shares sink 3.98 percent, while chip giant SK hynix retreated 3.33 percent. In contrast, Samsung Electro-Mechanics, an affiliate of Samsung Electronics, rose 4.52 percent, and battery maker LG Energy Solution gained 4.22 percent.
The Korean won was trading at 1,538.4 won against the U.S. dollar, down 6.4 won from the previous session as of 9:15 a.m.