The Korea Composite Stock Price Index (KOSPI) rose 0.4 percent to 1,984.33 points as of 0241 GMT. It jumped 1.6 percent a day earlier as the yen firmed, helping South Korean exporters.

"There is little change seen...the index saw a steep gain yesterday, and with the G20 meeting coming later this week the main board is not likely to move drastically in one direction until next week, said Kim Young-il, an analyst at Daishin Securities.

The Bank of Korea held interest rates steady at 2.75 percent on Thursday for a fourth straight month, in line with expectations and having little impact on the market.

Steelmakers were in favour for a second straight session, with POSCO up 1.5 percent while Dongbu Steel Co Ltd rose 7 percent.

"Steelmakers' profitability is seen improving from the second quarter as unfavourable factors such as the latest cut in automotive steel sheet pricing have already come to pass," said Kim Kang-oh, an analyst at Hanwha securities.

Advancing shares outnumbered decliners 433 to 335 near mid-session.

The KOSPI 200 benchmark of core stocks was up 0.5 percent, while the junior KOSDAQ edged 0.6 percent higher. Monthly KOSPI 200 index options and options for individual stocks are due to expire later in the day.