South Korean stocks retreated for second straight day on Wednesday as investors took to the sidelines ahead of the release of US consumer price data that may give more clues about the Federal Reserve's next move. The Korean won fell against the US dollar.

The benchmark Korea Composite Stock Price Index (KOSPI) declined 31.65 points, or 0.97 percent, to close at 3,216.18 points.

Trading volume was moderate at about 1.9 billion shares worth some 16.9 trillion won ($15.2 billion), with losers outnumbering gainers 571 to 287.

Foreigners sold a net 329 billion won, while retail investors bought 788 billion won. Institutions offloaded a net 458 billion won.

The key stock index slumped on a slew of data pointing to potentially higher inflation down the road.

The Bank of Korea said that South Korea's economy grew 1.7 percent in the first quarter from three months earlier, 0.1 percentage point higher than earlier expected.

China's producer price index in May exceeded the consensus amid rising commodity prices, adding to the global price pressures, although consumer prices grew slower than expected.

"Investors seem to be waiting for tomorrow's release of the May consumer price index and for the FOMC meeting next week," Shinhan Financial analyst Choi Yoo-joon said.

Most large caps retreated in Seoul, led by losses of bio, steel and tech shares.

Market bellwether Samsung Electronics shed 0.98 percent to 81,100 won, and No. 2 chipmaker SK hynix dipped 3.92 percent to 122,500 won.

Internet portal operator Naver moved down 1.1 percent to 358,500 won, and giant pharmaceutical firm Samsung Biologics retreated 2.46 percent to 834,000 won.

Top automaker Hyundai Motor lost 1.64 percent to 239,500 won, and leading chemical firm LG Chem decreased 0.74 percent to 802,000 won.

The local currency closed at 1,115.4 won against the US dollar, down 1.2 won from the previous session's close. (Yonhap)