China became South Korea's second-largest investment destination last year, relegating the European Union to the third spot, central bank data showed Thursday.

South Korea's external investment, which includes stocks and bonds, reached $716.6 billion at the end of last year, up $95.5 billion from the previous year, according to the data compiled by the Bank of Korea.

South Korean investment in the U.S. reached $173.6 billion at the end of last year, the largest among other regions with a 24.2 percent portion, followed by China with $132.4 billion and the EU with $127.2 billion.

South Korea's investment in China was $64.1 billion in 2010, but its size has more than doubled over the past four years, the data showed.

South Korea's direct investment in China reached $69.6 billion at the end of last year, accounting for 52.5 percent of the total.

The central bank data also showed that foreigners' outstanding investment in South Korea stood at $998.3 billion at the end of last year, with the EU being the largest investor with $265.3 billion.

The U.S. was the second-largest investor with $261 billion at the end of last year, according to the central bank. (Yonhap)