South Korean stocks opened lower Monday as investors attempted to cash in gains from the key stock index's three-day advance.

The benchmark Korea Composite Stock Price Index (Kospi) fell 22.9 points, or 0.76 percent, to 2,992.16 points in the first 15 minutes of trading.

The Kospi got off to a lackluster start amid sell-offs in most sectors.

In Seoul, Samsung Electronics lost 0.86 percent to 69,500 won, and No. 2 chipmaker SK hynix retreated 1.42 percent to 97,000 won.

Top automaker Hyundai Motor declined 1.44 percent to 205,500 won, and internet portal operator Naver moved down 0.76 percent to 390,500 won. Leading chemical firm LG Chem traded flat.

Among gainers, electric car battery maker Samsung SDI added 1.26 percent to 721,000 won, and SK Innovation increased 0.39 percent to 259,500 won.

The local currency was trading at 1,186.15 won against the US dollar, down 3.75 won from the previous session's close. (Yonhap)