South Korea’s KOSPI just had the kind of quarter that makes index fund investors feel like geniuses. The benchmark surged roughly 68% in Q2 2026, its best quarterly showing since the rebound from the Asian financial crisis in 1998.
The index climbed from around 5,000 to over 9,000, notching record highs in June. Year-to-date gains have stretched to nearly 100%, making the KOSPI one of the best-performing major indices on the planet this year.
The semiconductor story driving the rally
The engine behind this move isn’t mysterious. Samsung Electronics and SK Hynix, South Korea’s twin pillars of chipmaking, are projected to drive between 52% and 68% of KOSPI profit growth, according to analyst models. Both companies sit at the center of a global feeding frenzy for high-bandwidth memory, or HBM, the specialized chips that power the AI infrastructure buildout.
Samsung and SK Hynix are two of only three companies worldwide capable of manufacturing HBM at scale, giving South Korea an outsized role in what is arguably the defining technology trend of the decade.
