The country's authorities are closely monitoring the financial market, the finance ministry said Thursday.
The ministry also said it is "undesirable" to see an excessive one-sided movement in currency exchange rates.
"It is not desirable for market volatility to intensify due to a short-term one-sided movement in any direction," the ministry said in a memo to reporters.
"Therefore, we are closely monitoring foreign capital flows and transactions situations in the financial markets at home and abroad."
The Korean won rose to its highest mark against the dollar in nearly six years on Wednesday and opened higher on Thursday.
By Kim Yon-se and news reports (firstname.lastname@example.org)