Exports are expected to reach Imports are estimated to have gone up 26.5 percent on-year in September to $49.8 billion, resulting in a trade surplus of $5.3 billion.
South Korea will release its official trade data Friday.
In August, South Korea's exports have extended their gains to 10 months by rising 35 percent on-year.
South Korean stocks opened lower Tuesday, tracking a weak session on Wall Street, as investors assess a recent spike in coronavirus cases.
The benchmark Korea Composite Stock Price Index (Kospi) fell 4.35 points, or 0.14 percent, to 3,129.29 points in the first 15 minutes of trading.
Overnight, the tech-heavy Nasdaq composite lost 0.52 percent and the S&P 500 fell 0.28 percent, while the Dow Jones Industrial Average added 0.21 percent amid rising US Treasury yields.
Local stocks got off to a muted start as investor sentiment was also weighed down by a surge in new virus cases after an extended holiday last week.
Top cap Samsung Electronics dipped 0.39 percent, and No. 2 chipmaker SK hynix remained unchanged.
Internet portal operator Naver retreated 1.86 percent, while messaging giant Kakao added 0.42 percent.
Leading chemical firm LG Chem traded flat, while battery maker SK Innovation gained 1.39 percent after the company said it would build three electric vehicle battery plants in the United States with Ford.
Top automaker Hyundai Motor lost 0.49 percent, while pharmaceutical firm Samsung Biologics slipped 2.61 percent.
The local currency was trading at 1,180.7 won against the US dollar, down 3.9 won from the previous session's close. (Yonhap)