Asian semiconductor stocks surged as the artificial intelligence (AI) boom drove record gains for major chipmakers in both South Korea and Japan. On May 11, 2026, South Korea's benchmark KOSPI index hit a record intraday high, propelled by a 15% jump in SK Hynix shares and strong performance from Samsung Electronics. These two companies, the largest on the KOSPI, benefited from investor optimism regarding their critical role in supplying memory chips for AI applications [1]. The KOSPI index has risen more than 87% year to date, reflecting robust global demand for AI-linked semiconductor stocks and setting a bullish tone for Seoul's market [1]. Technical indicators confirmed the index's decisive move above historical resistance, with analysts recommending close monitoring of support levels due to the sharp rise and potential for consolidation [1].
In Japan, Kioxia's share price has soared 24 times year on year and nearly quintupled in 2026 alone, outpacing much of the Japanese market and signaling a shift in industry leadership from automotive to semiconductor sectors [2]. The rally in Kioxia shares underscores the growing importance of advanced memory chips for AI and data centers, with the company viewed as a bellwether for Japan’s transition toward high-tech industries [2]. Market analysts attribute Kioxia’s surge to global memory shortages, rising chip prices, and robust AI-related demand, with expectations that the semiconductor upcycle will continue [2]. Kioxia has also expanded its international reach with a $490 million investment in Taiwanese DRAM supplier Nanya, while Bain Capital has reduced its ownership stake in the company to under 30% [2].
Both markets are experiencing strong bullish sentiment, with technical support levels rising alongside prices. In South Korea, traders cite the relentless global rush into AI-linked semiconductor stocks as a key driver, while in Japan, Kioxia's anticipated inclusion in the Nikkei 225 index is expected to attract further institutional interest [1][2]. Analysts in both countries advise investors to monitor developments in semiconductor earnings and AI technology trends, as these factors will likely determine the next phase of market direction [1][2].
Despite the rapid appreciation, some caution is advised regarding potential resistance at historical highs and the possibility of profit-taking, but the prevailing outlook remains positive as long as AI-driven demand persists [1][2].
CONCLUSION
The AI-driven surge in semiconductor stocks has propelled SK Hynix and Kioxia to record gains, reshaping market dynamics in both South Korea and Japan. With bullish sentiment prevailing and expectations of continued robust demand, the semiconductor sector is positioned as a key driver of Asian equity markets. Investors are advised to watch for further developments in AI technology and chipmaker earnings to gauge the sustainability of this momentum.