Asia's fourth-largest economy expanded 0.6 percent on-quarter in the April-June period, compared with a 1.1 percent expansion for the first quarter, according to the data from the Organization for Economic Cooperation and Development.
It was the 18th-highest on-quarter gain among 27 OECD member nations whose growth figures were available, down from eight three months earlier.
The average on-quarter growth rate of the OECD economies rose to 0.7 percent in the second quarter from 0.5 percent the previous quarter.
Of the total, 13 countries saw their growth pace expand, while the remainder suffered slowdowns or stagnation.
South Korea registered the third-highest quarterly drop after Finland with 0.8 percentage point and Slovakia with 0.7 percentage point, according to the data.
South Korea's nosedive in the second-quarter growth was attributed mainly to the fact that the economy had expanded at a much faster clip than expected.
Still, the central Bank of Korea sees the second-quarter economic expansion as not so bad in light of improvements in consumer spending and corporate capital spending.
However, concerns are growing that the recovery pace of South Korea's economy may lose traction down the road due to a spate of downside risks, such as North Korea's latest nuclear test and America's growing protectionism.
In a recent interview with Yonhap News Agency, Finance Minister and Deputy Prime Minister for Economic Affairs Kim Dong-yeon said the government will leave no stone unturned to achieve its growth target of 3 percent for this year. (Yonhap)