Seoul shares rose on Tuesday for a seventh consecutive session, posting their highest close in more than a decade, as technology titles such as Hynix Semiconductor gained amid hopes for better second-half earnings.
But concerns about the impact of higher energy costs on corporate profits capped gains after crude oil prices rose to a record high.
SK Telecom Co fell 2.81 percent ahead of the sale of a $1 billion stake in the mobile operator held by SK Corp A source familiar with the deal told Reuters pricing was expected later on Tuesday.
The benchmark Korea Composite Stock Price Index (KOSPI) rose 0.26 percent to 1,118.83, its highest close since ending at 1,120.63 on November 17, 1994, according to data from the Korea Exchange data.
Concerns about energy costs hit manufacturers, sending top local automaker Hyundai Motor Co down 0.56 percent to end at 70,700 won.
South Korea's state-run power provider Korea Electric Power Corp fell 0.16 percent to 35,600 won, while shares in Korean Air Co, the biggest local carrier, fell 0.49 percent to end at 20,300 won.
Select technology stocks gained, tracking firmer US peers, with Hynix Semiconductor Inc surging 4.67 percent to close at 24,650 won.
LG.Philips LCD Co Ltd climbed 3.38 percent to 49,000 won as investors returned to the stock after it completed a stake sale last month, analysts said.
Other blue chips were also higher, with POSCO Co Ltd, the world's fifth-biggest steel maker, rising 0.73 percent to 207,500 won amid easing worries about steel prices.
Trade volume reached 557 million shares worth 3.1 trillion won ($3.02 billion) compared to 501 million shares worth 3.0 trillion won on Monday. Losers led gainers by 433 to 301 with 74 titles ending flat.
Foreign investors bought a net 34.1 billion won in shares on the main bourse, while retail investors sold a net 68.3 billion won. Institutional investors sold a net 43.8 billion won.
The September KOSPI 200 futures index rose 0.70 point to 144.40 and the underlying KOSPI 200 spot index gained 0.34 point to 144.30.
South Korea's junior and tech heavy Kosdaq market fell 0.56 percent to finish at 541.78.