An electronic board showing the Korea Composite Stock Price Index (Kospi) at a dealing room of the Hana Bank headquarters in Seoul on Thursday. (Yonhap)

South Korean stocks opened slightly higher Thursday as worries about an economic slowdown from the US Federal Reserve's widely expected interest rate hikes sapped investor appetite despite reports of sound corporate earnings this week.

The Korea Composite Stock Price Index (KOSPI) added 9.57 points, or 0.36 percent to trade at 2,648.63 in the first 15 minutes of trading.

Shares traded mixed across the board. Market heavyweight Samsung Electronics was up 0.15 percent to 65,100 won, after reporting its best first-quarter operating profit of 14.1 trillion won ($11.1 billion) in four years.

LG Energy Solution, the second-largest listed firm by market cap, slipped 0.12 percent to 417,500 won.

South Korea's top chemical maker LG Chem jumped about 4 percent, while top internet portal operator Naver shed about 0.2 percent.

The local currency was trading at 1,265.30 won against the US dollar as of 9:15 a.m., down 0.1 won from Wednesday's close. (Yonhap)