During Nov. 1-20, exports dropped 7.7 percent from a year earlier, the data showed.
In October, exports by Asia's fourth-largest economy shrank by a revised 15.9 percent over a year earlier, their worst annual decline in more than six years. For the first 20 days of October, exports dropped 16.0 percent.
Data that the Korea Customs Service published on its website showed exports during the Nov. 1-20 period dropped to $27.39 billion while imports slid 13 percent to $24.83 billion.
The customs agency did not provide figures such as for destination for the Nov. 1-20 exports. China is South Korea's biggest export market, taking one-quarter of the smaller neighbour's total shipments. The second biggest customer is the United States.
On Dec. 1, South Korea will release preliminary export and import figures for all of November. It will be the first major exporting economy to report November numbers, which can provide an early clue on the state of global demand.