The revised real GDP, adjusted for inflation, expanded 0.3 percent in the July-September quarter from three months earlier, down from the rises of 0.6 percent in the first quarter and 0.7 percent in the second quarter each, according to the Bank of Korea (BOK).
The country's export gained 1.1 percent in the third quarter on a quarterly basis, while import advanced 6.0 percent on higher energy import cost.
The outbound shipment was forecast to decline in the fourth quarter. The export plunged 14.0 percent in November, after sliding 5.7 percent in October.
Private consumption grew 1.7 percent during the July-September quarter as the eased measures against the COVID-19 pandemic raised the demand for eatery and lodging services and semi-durable goods for outside activities.
Facility investment jumped 7.9 percent on solid demand for semiconductor and transport equipment, but investment in the construction sector reduced 0.2 percent on the faltering engineering construction.
Real gross national income (GNI), which measures the total income earned at home and abroad by businesses and people, retreated 0.7 percent in the third quarter.
The GDP deflator, or the ratio of nominal GDP to real GDP to gauge the price change for all the goods and services produced in the country, was up 0.2 percent during the cited quarter.
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