The won's advance against the dollar weighed on technology and auto exporters. Shares in LG Display fell 4.5% and Hynix Semiconductor shed 2.6%. The country's top car maker Hyundai Motor lost 4.3%.
"Lately memory chip and liquid crystal display (LCD) issues have been drumming up a lot of appetite but LG Electronics is neither. Also its smartphone business outlook is growing weaker, amid rising competition such as Google's smart phone," said Kim Woon-ho, a market analyst at Prudential Investment & Securities.