The benchmark Korea Composite Stock Price Index (KOSPI) rose 5.76 points, or 0.24 percent, to close at 2,360.81.
Trading volume was moderate at 874 million shares worth 10.5 trillion won ($9.3 billion), with gainers outnumbering losers 436 to 408.
Foreigners bought a net 37 billion won, while retail investors sold a net 270 billion won. Institutions purchased a net 225 billion won.
Stocks got off to a muted start amid lingering uncertainties over the ongoing talks for the new US virus relief package.
But gains by auto and banking heavyweights led the KOSPI's hike, as investors pinned high hopes for a flurry of upbeat earnings reports scheduled for next week.
Posco, LG Chem and banking large caps revealed estimate-beating earnings this week, fueling optimism for the third-quarter earnings to be released next week.
In Seoul, large caps closed mixed.
Market bellwether Samsung Electronics added 0.17 percent to 60,200 won, and No. 2 chipmaker SK hynix advanced 0.72 percent to 83,900 won.
Top pharmaceutical firm Samsung Biologics dipped 3.34 percent to 636,000 won, but Celltrion edged up 0.21 percent to 238,000 won.
Internet portal giant Naver lost 2.22 percent to 286,500 won, with its rival Kakao down 2.58 percent to 340,000 won.
Leading chemical maker LG Chem gained 1.72 percent to 650,000 won, while rechargeable battery maker Samsung SDI shed 1.16 percent to 424,500 won.
Hyundai Motor, the country's largest automaker, added 2.77 percent to 167,000 won, and top steelmaker Posco spiked 4.76 percent to 220,000 won.
The local currency closed at 1,132.9 won per dollar, flat from the previous session's close.
Bond prices, which move inversely to yields, closed higher. The yield on three-year Treasurys lost 1.5 basis points to 0.910 percent, and the return on the benchmark five-year government bond fell 1.8 basis points to 1.191 percent. (Yonhap)