South Korea's Kospi index plunged 5% on Tuesday, sliding to 6,448.86 and extending a brutal correction that has erased more than 31% of its value from the June peak of 9,000.
The sharp decline marks a continuation of the selling pressure that recently pushed the benchmark into bear-market territory, defined as a drop of more than 20% from recent highs.
The market, which had been widely celebrated as the world's best-performing equity market in 2026, is now grappling with a severe repricing of risk.
The selloff follows a session of heavy losses on Wall Street, where technology stocks led declines amid broader global caution.
The correlation between US tech weakness and Asian market stress has intensified, with South Korea's export-oriented economy proving particularly vulnerable to shifts in global sentiment.
The rapid deterioration in the Kospi underscores how quickly momentum can reverse in markets that have experienced parabolic rallies.