The benchmark Korea Composite Stock Price Index added 17.48 points, or 0.74 percent, to 2,377.76. Trade volume was moderate at 283.1 million shares worth 6.3 trillion won ($5.8 billion), with losers slightly outnumbering advancers 403 to 397.
The broad index opened higher taking a cue from overnight gains on Wall Street. On Wednesday (local time), US stocks closed at fresh record highs, with the S&P 500 inching up 0.1 percent and the Dow gaining 0.2 percent.
"The local stock market closed higher on the back of Wall Street gains and a buying spree by individuals despite a selling spree by both foreigners and institutions," said Lee Yeong-gon, a Hana Financial Investment analyst.
Most large-cap stocks ended mixed, with tech and auto shares leading the gain.
Top cap Samsung Electronics ended at 2,515,000 won, up 1.37 percent from the previous session's close. Its smaller rival LG Electronics added 0.57 percent to 87,900 won. Flat panel maker LG Display moved up 2.74 percent at 33,800 won.
Chipmaker SK hynix also increased 1.37 percent to 76,800 won, and top portal operator Naver soared 4.94 percent to end at 765,000 won.
LG Innotek, an electronic parts maker that supplies parts for Apple, rose 2.67 percent to close at 173,000 won ahead of the new iPhone launch slated for later this year.
Auto stocks also closed higher, with leading automaker Hyundai Motor adding 2.24 percent to 137,000 won and its sister company, Kia Motors, moving up 1.16 percent to 30,600 won.
Shares of pharmaceutical companies gained ground, with Samsung BioLogics, a biopharmaceutical affiliate of Samsung Group, jumping 6.93 percent to end at 324,000 won.
The local currency closed at 1,132.60 won against the US dollar, down 4.10 won from Wednesday's close.
Bond prices, which move inversely to yields, ended mixed. The yield on three-year Treasurys remained unchanged at 1.742 percent and the return on the benchmark five-year government bonds lost 0.4 basis point to 1.945 percent. (Yonhap)