Ho Chi Minh City led with 5,294 new cases, followed by Binh Duong Province (4,129) and Dong Nai Province (618).
Wednesday marked the seventh day in a row Vietnam has recorded over 10,000 cases in a day.
This brings the total number of cases in the fourth Covid-19 wave to 377,245. Among them 167,147 have been discharged.
335 deaths were confirmed Wednesday, most of them in HCMC. The Covid-19 death tally is now at 9,349, or 2.5 percent of infections.
Vietnam has vaccinated 18.09 million people, among them 2.04 million have received two doses.