Vietcombank sold the dollar at VND24,820 Tuesday, down 0.08% from Monday.
The State Bank of Vietnam set its reference rate at VND24,014, up 0.08%.
The greenback gained 0.20% to VND25,350 on the black market.
It has increased over the dong by 1.64% since the beginning of the year.
Globally the dollar traded on the back foot on Tuesday, as markets looked ahead to a week of U.S. economic data that will provide fresh signals on how soon the Federal Reserve may begin cutting interest rates, Reuters reported.
The U.S. dollar index , which measures the currency against a basket of peers including the euro and yen, traded flat at 103.77 in Asian time, following a 0.17% slide on Monday.