[Sep 21, 2026 Korea Market Closing] AMD Joins $1 Trillion Club on AI Chip Boom—Will South Korean Markets Catch the Semiconductor Wave? KOSPI and KOSDAQ Close Higher as AMD Hits Record High Amid Global AI Chip Boom

Market Summary

The South Korean stock market staged a robust rebound on September 21, 2026, fueled by the global artificial intelligence chip craze and AMD crossing the $1 trillion market capitalization milestone.

• 📌 [Global Market Alignment]: US-listed AMD surged to record highs on soaring data center revenues, lifting sentiment across South Korean semiconductor plays.
• 📌 [Steady Index Advance]: KOSPI finished up 1.65% at 7,007.72 points, while KOSDAQ gained 1.11% to close at 836.27 points.
• 📌 [Divergent Sentiment]: The Fear & Greed Index stood at 34, indicating ongoing market ‘Fear’, yet strong earnings momentum in core innovation technology stocks strongly supported the indices.

With the clear megatrend of expanding global AI infrastructure investments confirmed, focusing on stock-specific earnings differentiation remains a winning strategy.

Author’s Opinion & Investment Strategy

Observing today’s market action made me realize once again the massive influence that earnings surprises from global semiconductor giants hold over the South Korean stock market.

• 💡 [Earnings-Focused Approach]: Even when overall market sentiment registers as fearful, companies proving solid fundamentals and surging data center revenue continue to hold their ground.
• 💡 [Avoid Emotional Trading]: Rather than chasing rallies blindly just because indices rebound, investors should vet portfolios for stocks backed by robust global order momentum.
• 💡 [Strict Risk Management]: In volatile market environments, deploying capital in tranches rather than all at once is essential for proper risk mitigation.

Especially for beginners, developing the habit of calmly examining the fundamentals of profitable companies rather than getting distracted by news headlines is vital.

Deep Dive of News Channels

① Naver Pay Securities - Summary

Acted as a reliable compass for investors by delivering real-time movements of major domestic and global indices alongside detailed capital flow trends.

• 🔹 [Index Strength]: Detailed the synchronized upward trend and trading volume patterns of KOSPI and KOSDAQ.
• 🔹 [Sector Trends]: Focused heavily on price shifts across large-cap tech and semiconductor stocks.

• AMD: Achieved a 107% surge in data center revenue, hitting a record intraday high and entering the $1 trillion market cap club.
• Samsung Electronics: Acted as the bellwether of the South Korean stock market, leading index gains amid the global semiconductor tailwind.
• SK Hynix: Captured strong investor attention driven by expectations of rising demand for AI chips and High Bandwidth Memory (HBM).
• Coupang: Drew market scrutiny regarding internal corporate management systems following reports on workplace harassment filings.

② Yonhap News Economy - Summary

Delivered in-depth reports on domestic economic and social indicators, including the widening trade deficit in pet food and workplace grievance filings.

• 🔹 [Pet Food Trade Balance]: Reported that pet food trade deficits reached 1.3 trillion KRW over the past 5 years, with imports doubling exports.
• 🔹 [Employment & Social Issues]: Highlighted reports on single-household social isolation and fact-checks regarding corporate hiring criteria.

• Coupang Affiliates: Ranked among the top workplaces for reported workplace harassment cases submitted to the Ministry of Employment and Labor.
• Pet Food Industry Entities: Highlighted the growth potential and structural challenges of a domestic market heavily reliant on pet food imports.
• Major Corporate Recruiters: Re-examined recruitment standards through fact-checks regarding age and university background restrictions in hiring.
• Global Cultural Exchange Organizations: Expanded global perspectives through the Ubuntu Column analyzing political and social shifts in Africa.

③ Maeil Business News - Summary

Comprehensive coverage featuring AMD’s $1 trillion milestone, regulatory challenges regarding data usage for AI innovation, and domestic political updates.

• 🔹 [Overseas Tech Earnings]: Reported that AMD surged 10% on AI chip strength, achieving an 180% year-to-date gain.
• 🔹 [Domestic Politics & Policy]: Promptly conveyed the presidential chief of staff’s resignation offer and updates on ministerial nominees.

• AMD: Highlighted CEO Lisa Su’s outlook and surging data center sales that position the company as a leader in global tech.
• Yulchon: Analyzed the policy challenges of introducing ‘original data usage exceptions’ to balance AI innovation with privacy.
• Office of the President: Expressed commitment to refining state affairs with a more humble approach during senior secretary meetings.
• Legal & Consulting Bodies: Assessed the necessity of legal and institutional reforms for AI data utilization from an expert perspective.

Top 5 Key Companies of the Day

1. AMD: Soared 10% to record highs and joined the $1 trillion market cap club, powered by a 107% surge in data center revenue amid the AI chip boom.
2. Samsung Electronics: Anchored steady index performance as the flagship heavyweight of the South Korean stock market amid global semiconductor tailwinds.
3. SK Hynix: Benefited from robust optimism surrounding rising demand for high-value memory chips tied to expanding artificial intelligence infrastructure.
4. Coupang: Drew focal attention concerning corporate governance and internal management standards after being cited in workplace harassment grievance reports.
5. Pet Food Industry Entities: Navigating high import dependency amidst a growing pet-owning population, highlighting structural challenges in domestic pet food trade.

Source & Disclaimer

• Source: Naver Pay Securities, Yonhap News Economy, Maeil Business News
• This content represents a personal opinion and is for reference only.