The index moved up in line with overnight gains on Wall Street as reports indicated Washington may be considering cutting some tariffs on Chinese-made goods to secure a beneficial long-term trade deal with Beijing.

"Investor sentiment swung between high and low in response to the latest development in US-China trade issues, while China's stimulus program gave relief to worries over its growth," Yoon Jeong-seon, an analyst at KB Investment & Securities, said.

Foreigners and institutions bought a net 108.52 billion won and 103.69 billion won worth of local stocks, respectively, while retail investors sold a net 210.5 billion won.

Tech shares were mixed. Market bellwether Samsung Electronics rose 0.83 percent to 42,300 won, while SK hynix shed 0.46 percent to 64,600 won.

Auto shares continued to rally after the government on Thursday unveiled its hydrogen economy plan featuring fuel cell electric vehicles.

Top automaker Hyundai Motor, which makes the FCEV NEXO, increased 1.16 percent to 131,000 won, and its parts maker Hyundai Mobis climbed 1.45 percent to 210,000 won.

Bio shares were also bullish. 

Pharmaceutical giant Celltrion moved up 2.81 percent to 201,000 won, and Samsung Biologics, Samsung's health care unit, increased 3.63 percent to 400,000 won. 

In contrast, No. 1 steelmaker POSCO slipped 0.19 percent to 262,500 won, and the state-run Korea Electric Power Corp. declined 1.88 percent to 33,850 won.

The local currency closed at 1,121.9 won against the US dollar, up 0.6 won from Thursday's close.

Bond prices, which move inversely to yields, ended lower. The yield on three-year Treasurys added 1.9 basis points to 1.814 percent, and the return on benchmark five-year government bonds increased 2.4 basis points to 1.895 percent. (Yonhap)