Vietcombank sold the dollar at VND24,390, down 0.25% from Sunday.
The State Bank of Vietnam kept its reference rate stable at VND23,939.
The greenback fell 0.12% to VND24,620 on the black market.
It has increased by 2.78% against the dong since the beginning of the year.
Globally the dollar started the week on a shaky footing on Monday as markets took stock of cautious remarks from Federal Reserve Chair Jerome Powell as they waited on a key employment report that could influence the outlook for U.S. interest rates, Reuters reported.
The U.S. dollar index , which tracks the currency against six major counterparts, was last hovering around Friday's close at 103.28.
Bitcoin grabbed the spotlight in the Asian morning, reaching the $40,000 level for the first time in over a year.