Most of the new cases were detected in Nghe An Province, at 56,192, including 45,896 cases detected on previous days that were only added to the national database now. Bac Giang recorded 33,147 new cases, including 30,353 cases recorded earlier.
Hanoi recorded 31,365 cases, the highest single-day tally to date.
In the past 24 hours, 109 Covid-19 patients have died, including eight in Hanoi.
Since the pandemic started last year, the death toll in Vietnam has climbed to 41,086 or 0.9 percent of all infections.
In the latest wave that hit the country in late April, more than 5.03 million cases have been confirmed and 2.85 million of them have recovered.
So far, 79.3 percent of the population have received two vaccine doses.