Foreign investors sold a net 2.4 trillion won ($2.12 billion) worth of local stocks last month, according to the data by the Financial Supervisory Service.
Investors from the US, Singapore and Britain were among net sellers of local stocks last month, the data showed.
North Korea has rattled the global community since July, when it successfully test-launched what it claimed were two intercontinental ballistic missiles. Since then, it fired an intermediate range ballistic missile over Japan and conducted its sixth and most powerful nuclear test earlier this month.
At the end of August, foreign investors held a total of 596.2 trillion won worth of local stocks, accounting for 33.2 percent of the nation's market capitalization.
Foreign investors also sold a net 2.1 trillion won worth of local bonds last month.
At the end of August, foreign investors' holdings of local debt stood at 104.4 trillion won, accounting for 6.3 percent of the bond market. (Yonhap)